04/07/2021 | Press release | Distributed by Public on 04/07/2021 14:55

Supplemental Prospectus (SEC Filing - 424B5)

astc-424b5.htm

Filed pursuant to Rule 424(b)(5)

Registration Statement No. 333-253835

The information in this preliminary prospectus supplement is not complete and may be changed. A registration statement relating to these securities has been filed with the Securities and Exchange Commission and is effective. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED APRIL 7, 2021

PROSPECTUS SUPPLEMENT

(To Prospectus Dated March 15, 2021)

Shares of Common Stock

Pre-funded Warrants to Purchase Shares of Common Stock

Underwriter Warrants to Purchase Shares of Common Stock

We are offering up to shares of our common stock, par value $0.001 per share, pursuant to this prospectus supplement and the accompanying prospectus. The public offering price for each share of common stock is $ .

We are also offering pre-funded warrants, or the Pre-funded Warrants (and the shares of common stock issuable from time to time upon exercise of the Pre-funded Warrants), to those purchasers whose purchase of shares of common stock in this offering would result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding shares of common stock following the consummation of this offering in lieu of the shares of common stock that would result in such excess ownership. Each Pre-funded Warrant will be exercisable for one share of common stock at an exercise price of $0.001 per shares of common stock. The public offering price is $ per Pre-funded Warrant, which is equal to the public offering price per share less $0.001. Each Pre-funded Warrant will be exercisable upon issuance and will expire when exercised in full. There is no established public trading market for the Pre-funded Warrants, and we do not expect a market to develop. We do not intend to apply for listing of the Pre-funded Warrants on any securities exchange or nationally recognized trading system. Without an active trading market, the liquidity of the Pre-funded Warrants will be extremely limited.

Our common stock is listed on the Nasdaq Capital Market under the symbol 'ASTC'. On April 06, 2021, the last reported sale price as reported on the Nasdaq Capital Market was $2.18 per share.

The public offering price per share of common stock and the public offering price per Pre-funded Warrant will be determined between us, the underwriter, and investors based on market conditions at the time of pricing, and may be at a discount to the current market price of our shares of common stock.

The offering is being underwritten on a firm commitment basis. The underwriter may offer the shares of common stock and Pre-funded Warrants from time to time to purchasers directly or through agents, through brokers in brokerage transactions on The Nasdaq Capital Market, to dealers in negotiated transactions or in a combination of such methods of sale, or otherwise, at fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices related to such prevailing market prices.

Investing in our common stock involves a high degree of risk. See 'Risk Factors' beginning on page S-10 of this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

We have granted the underwriter an option for a period of up to 30 days from the date of this prospectus supplement to purchase up to additional shares of our common stock at the public offering price, less underwriting discounts and commissions. If the underwriter exercises the option in full, the total underwriting discounts and commissions payable by us will be $ and the total proceeds to us, before expenses, will be $ .

Delivery of the shares of common stock being offered pursuant to this prospectus supplement and the accompanying prospectus is expected to be made on or about , 2021, subject to the satisfaction of certain closing conditions.

H.C. Wainwright & Co.

The date of this prospectus supplement is , 2021.

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TABLE OF CONTENTS

Prospectus Supplement

Prospectus

You should rely only on the information we have provided or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not authorized anyone to provide you with information different from that contained or incorporated by reference in this prospectus supplement or the accompanying prospectus.

This prospectus supplement and any later prospectus supplement is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

You should assume that the information contained in this prospectus supplement and in any other prospectus supplement is accurate only as of their respective dates and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus supplement or any other prospective supplement for any sale of securities.

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is the prospectus supplement, including the documents incorporated by reference, which describes the specific terms of this offering. The second part, the accompanying prospectus, including the documents incorporated by reference, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. Before you invest, you should carefully read this prospectus supplement, the accompanying prospectus, all information incorporated by reference herein and therein, as well as the additional information described under 'Where You Can Find More Information' on page S-21 and 'Incorporation of Certain Information by Reference' on page S-22 of this prospectus supplement. These documents contain information you should consider when making your investment decision. This prospectus supplement may add, update, or change information contained in the accompanying prospectus. To the extent that any statement that we make in this prospectus supplement is inconsistent with statements made in the accompanying prospectus or any documents incorporated by reference, the statements made in this prospectus supplement will be deemed to modify or supersede those made in the accompanying prospectus and such documents incorporated by reference.

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and in any free writing prospectuses we authorize for use in connection with this offering. Neither we nor the underwriter have authorized any other person to provide you with any information that is different. If anyone provides you with different or inconsistent information, you should not rely on it. We are offering to sell, and seeking offers to buy, the securities offered hereby only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the securities offered hereby in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the securities offered hereby and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

The information appearing in this prospectus supplement, the accompanying prospectus or any related free writing prospectus that we authorize for use in connection with this offering is accurate only as of the date on the front of the document and any information we have incorporated by reference is accurate only as of the date of such document incorporated by reference, regardless of the time of delivery of this prospectus supplement or any related free writing prospectus, or any sale of a security. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein contain summaries of certain provisions contained in some of the documents described herein and therein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus supplement and the accompanying prospectus are a part, and you may obtain copies of those documents as described below under the heading 'Where You Can Find More Information.'

Unless the context otherwise requires, (i) references to the 'Company,' 'we,' 'our,' or 'us' refer to Astrotech Corporation and its subsidiaries and (ii) references to 'common stock' refer to the common stock, par value $0.001 per share, of the Company.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein may contain forward looking statements that involve risks and uncertainties. All statements other than statements of historical fact contained in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, including statements regarding future events, our future financial performance, business strategy, and plans and objectives of management for future operations, are forward-looking statements. We have attempted to identify forward-looking statements by terminology including 'anticipates,' 'believes,' 'can,' 'continue,' 'could,' 'estimates,' 'expects,' 'intends,' 'may,' 'plans,' 'potential,' 'predicts,' 'should,' or 'will' or the negative of these terms or other comparable terminology. Although we do not make forward looking statements unless we believe we have a reasonable basis for doing so, we cannot guarantee their accuracy. These statements are only predictions and involve known and unknown risks, uncertainties and other factors, including the risks outlined under 'Risk Factors' or elsewhere in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, which may cause our or our industry's actual results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Moreover, we operate in a highly regulated, very competitive, and rapidly changing environment. New risks emerge from time to time and it is not possible for us to predict all risk factors, nor can we address the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause our actual results to differ materially from those contained in any forward-looking statements.

We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy, short term and long-term business operations, and financial needs. These forward-looking statements are subject to certain risks and uncertainties that could cause our actual results to differ materially from those reflected in the forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed (i) in our Annual Report on Form 10-K for the fiscal year ended June 30, 2020, (ii) in this prospectus supplement and the accompanying prospectus, and in particular, the risks discussed below and under the heading 'Risk Factors' and (iii) those discussed in other documents we file with the SEC. The following discussion should be read in conjunction with the consolidated financial statements for the fiscal years ended June 30, 2020 and 2019 and notes incorporated by reference herein. We undertake no obligation to revise or publicly release the results of any revision to these forward-looking statements, except as required by law. In light of these risks, uncertainties and assumptions, the forward-looking events and circumstances discussed in this prospectus may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statement.

You should not place undue reliance on any forward-looking statement, each of which applies only as of the date of this prospectus supplement. You are advised to consult any further disclosures we make on related subjects in our reports on Forms 10-Q, 8-K and 10-K filed with the SEC.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights certain information about us, this offering and selected information contained elsewhere in this prospectus supplement and in the documents incorporated by reference. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our shares of common stock. For a more complete understanding of our company and this offering, we encourage you to read and consider carefully the more detailed information contained in or incorporated by reference in this prospectus supplement, including the information contained under the heading 'Risk Factors' beginning on page S-10 of this prospectus supplement, and the information included in any free writing prospectus that we have authorized for use in connection with this offering.

Throughout this prospectus supplement, the terms 'we,' 'us,' 'our,' and 'our company' refer to Astrotech Corporation, a Delaware corporation, and its consolidated subsidiaries unless the context requires otherwise.

Company Overview

Our efforts are focused on commercializing its platform mass spectrometry technology through our wholly-owned subsidiaries:

Our Business Units

Astrotech Technologies, Inc.

ATI owns and licenses the AMS Technology, the platform mass spectrometry technology originally developed by 1^st Detect. The intellectual property includes 32 granted patents and two additional patents in process along with extensive trade secrets. With a number of diverse market opportunities for the core technology, ATI is structured to license the intellectual property for different fields of use. ATI currently licenses the AMS Technology to three wholly-owned subsidiaries of Astrotech, including to 1^st Detect for use in the security and detection market, to AgLAB for use in the agriculture market, and to BreathTech for use in breath analysis.

1^st Detect Corporation

1^st Detect, an exclusive licensee of ATI for the security and detection market, has developed the TRACER 1000™, the world's first mass spectrometer ('MS') based explosives trace detector ('ETD') certified by the European Civil Aviation Conference ('ECAC'), designed to replace the ETDs used at airports, cargo facilities, secured facilities, and borders worldwide. We believe that ETD customers are unsatisfied with the currently deployed ETD technology, which is driven by ion mobility spectrometry ('IMS'). We believe that IMS-based ETDs are fraught with false positives, as they often misidentify personal care products and other common household chemicals as explosives, causing unnecessary delays, frustration, and significant wasted security resources. In addition, there are hundreds of different types of explosives, but IMS-based ETDs have a very limited threat detection library reserved only for those several explosives of largest concern. Adding additional compounds to the detection library of an IMS-based ETD fundamentally reduces the instrument's performance, further increasing the likelihood of false alarms. In contrast, adding additional compounds does not degrade the TRACER 1000's detection capabilities, as it has a virtually unlimited and easily expandable threat library. With terrorist threats becoming more numerous, sophisticated, and lethal, security professionals have been looking for better instrumentation, and specifically for mass spectrometry, to address

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the evolving threats, but mass spectrometry has long been too expensive, too cumbersome, and not practical for security applications until the launch of the TRACER 1000.

In order to sell the TRACER 1000 to airport and cargo security customers in the European Union, ECAC certification is required. Certain other countries also accept ECAC certification. After receiving ECAC certification for the TRACER 1000 on February 21, 2019, we are now marketing to and taking orders from airports and cargo facilities outside of the U.S. that accept ECAC certification.

On June 26, 2019, we announced the official launch of the TRACER 1000, and on November 22, 2019, we announced our first commercial sale of TRACER 1000 units to a global shipping and logistics company.

In the United States, we are working with the TSA towards Air Cargo certification. On March 27, 2018, we announced that the TRACER 1000 was accepted into TSA's Air Cargo Screening Technology Qualification Test ('ACSQT') and, on April 4, 2018, we announced that the TRACER 1000 was beginning testing with TSA for passenger screening at airports. On November 14, 2019, we announced that the TRACER 1000 had been selected by the TSA's Innovation Task Force to conduct live checkpoint screening at Miami International Airport. With similar protocols as ECAC testing, we have received valuable feedback from all programs. Following ECAC certification and acceptance in the cargo market, testing for cargo security continued with the TSA. With the COVID-19 pandemic, all testing within the TSA was put on hold; however, cargo non-detection testing resumed during the summer of 2020, and we subsequently announced on September 9, 2020 that the TRACER 1000 passed the non-detection testing portion of the TSA's ACSQT. TSA cargo detection testing resumed during the fall of 2020 and continues to move forward. This is the next and final step to be listed on the Air Cargo Screening Technology List ('ACSTL') as an 'approved' device and, if approved, thereby approved for cargo sales in the United States. Given the deterioration in air traffic caused by the pandemic, we have determined to put TSA certification testing for passenger checkpoint security on indefinite hold.

Finally, on October 28, 2020, we announced that we had surpassed $1.0 million in purchase orders for the TRACER 1000 and an additional $1.0 million in future service and support commitments, also announcing DHL (Deutsche Post AG) as its largest flagship customer.

AgLAB Inc.

AgLAB, an exclusive licensee of ATI for the agriculture market, has developed the AgLAB-1000™ series of mass spectrometers for process control and in the detection of trace levels of solvents and pesticides. The AgLAB product line is a derivative of our core AMS Technology. The AMS Technology provides a significant competitive advantage due to its small size, rugged design, quick analysis, ease of use, and affordability. These attributes are valuable for agriculture applications in both processing facilities and in the field.

BreathTech Corporation

BreathTech, an exclusive licensee of ATI for breath analysis, is developing the BreathTest-1000™, a breath analysis tool to screen for VOC metabolites found in a person's breath that could indicate they may have an infection, including COVID-19 or pneumonia.

Development of the BreathTest-1000 follows our positive results in pre-clinical trials for the BreathDetect-1000™, a rapid self-serve breathalyzer that detects bacterial infections in the respiratory tract, including pneumonia. The pre-clinical trials were conducted in collaboration with UT Health San Antonio in 2017.

On October 20, 2020, we announced a joint development agreement with The Cleveland Clinic Foundation to explore leveraging the BreathTest-1000 to rapidly screen for COVID-19 or related indicators. The goal of the agreement is to develop a non-invasive device that will use breath samples to identify COVID-19 strains, with the potential to provide a low-cost, self-service screening option that could be deployed on a large-scale.

Recent Developments

On October 20, 2020, we issued a press release announcing that our subsidiary BreathTech Corporation signed a joint development and option agreement (the 'JDA') with the Cleveland Clinic Foundation (the 'Cleveland Clinic'). Pursuant to the JDA, we and the Cleveland Clinic will collaborate in efforts to develop a rapid breath test for coronavirus infection or

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related indicators, using our mass spectrometry technology and collection of data related thereto through an investigator initiated clinical study performed by the Cleveland Clinic.

On October 23, 2020, we consummated a public offering (the 'Public Offering') of 7,826,086 Shares, at an offering price of $2.30 per Share. The Public Offering resulted in gross proceeds of approximately $18.0 million before deducting the placement agent's fees and related offering expenses.

On October 30, 2020, we completed a registered direct offering (the 'Registered Offering') of 2,887,906 Shares, at an offering price of $2.15 per Share. The Registered Offering resulted in gross proceeds of approximately $6.2 million before deducting the placement agent's fees and related offering expenses.

As of February 9, 2021, we have sold 1,139,323 shares of common stock pursuant to an at-the-market agreement with the Placement Agent (the 'ATM Offering'). In connection with the sales of these shares of common stock, we have received net proceeds of approximately $3.5 million. The weighted-average sale price per share was $3.14.

On February 16, 2021, we completed a registered direct offering (the 'Registered Offering No. 2') of 2,845,535 Shares, at an offering price of $3.25 per Share. The Registered Offering No. 2 resulted in gross proceeds of approximately $9.25 million before deducting the placement agent's fees and related offering expenses.

On March 30, 2021, we announced that our Astrotech Technologies, Inc. subsidiary has entered into an agreement with Sanmina Corporation to manufacture its mass spectrometry products. Sanmina is a leading integrated manufacturing solutions provider for the Electronics Manufacturing Services market. As part of the relationship, Sanmina will manufacture 1^st Detect's TRACER 1000™. They have also agreed to manufacture AgLAB's AgLAB-1000™ and BreathTech's BreathTest-1000™ once those products are officially released.

On March 31, 2021, BreathTech signed an Investigator-Initiated Study Agreement (the 'Agreement') with the Cleveland Clinic. Pursuant to the Agreement, the Cleveland Clinic will use BreathTech's BreathTest-1000™ to compare exhaled breath from individuals who have tested positive on a COVID-19 polymerase chain reaction ('PCR') test with that from subjects who have had a negative COVID-19 PCR test. The goal of the pilot study will be to analyze different volatile organic compounds from the breath to evaluate the correlation with different disease states, and favorable results may require confirmation in a subsequent larger study.

Available Information

Our principal executive offices are located at 2028 E. Ben White Blvd., Suite 240-9530, Austin, Texas, 78741, and our telephone number is (512) 485-9530.

Our common stock trades on the Nasdaq Capital Market under the symbol 'ASTC'.

Our principal Internet address is www.astrotechcorp.com. Information contained on, or that can be accessed through, our website, is not, and shall not be deemed to be, incorporated in this prospectus supplement or considered a part thereof. We make available free of charge on www.astrotechcorp.com our annual, quarterly and current reports, and amendments to those reports, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at http://www.sec.gov.

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THE OFFERING

The number of shares of our common stock to be outstanding after this offering as shown above is based on 24,613,330 shares outstanding as of April 6, 2021 and excludes as of that date:

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RISK FACTORS

An investment in our securities involves a high degree of risk. This prospectus contains, and the prospectus supplement applicable to each offering of our securities will contain, a discussion of the risks applicable to an investment in our securities. Prior to making a decision about investing in our securities, you should carefully consider the specific factors discussed under the heading 'Risk Factors' in this prospectus and the applicable prospectus supplement, together with all of the other information contained or incorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under Item 1A, 'Risk Factors,' in our Annual Report on Form 10-K for the fiscal year ended June 30, 2020, filed with the SEC on November 8, 2020, and any updates described in our Quarterly Reports on Form 10-Q, all of which are incorporated herein by reference, and may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future and any prospectus supplement related to a particular offering. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. The occurrence of any of these known or unknown risks might cause you to lose all or part of your investment in the offered securities.

Risks Related to the Offering

Our stock price is volatile, and your investment may suffer a decline in value.

The closing market price for our common stock has varied between a high of $4.05 on February 10, 2021, and a low of $1.49 on September 23, 2020, in the twelve-month period ended April 6, 2021. As a result of fluctuations in the price of our common stock, you may be unable to sell your shares at or above the price you paid for them. The market price of our common stock is likely to continue to be volatile and subject to significant price and volume fluctuations in response to market, industry and other factors, including the risk factors described under the section captioned 'Risk Factors' contained in our Annual Report on Form 10-K for the year ended June 30, 2020 and our subsequent Quarterly Reports on Form 10-Q, all of which are incorporated by reference in this prospectus supplement in their entirety. The market price of our common stock may also be dependent upon the valuations and recommendations of the analysts who cover our business. If the results of our business do not meet these analysts' forecasts, the expectations of investors or the financial guidance we provide to investors in any period, the market price of our common stock could decline.

In addition, the stock markets in general, and the markets for technology stocks in particular, have experienced significant volatility that has often been unrelated to the financial condition or results of operations of particular companies. These broad market fluctuations may adversely affect the trading price of our common stock and, consequently, adversely affect the price at which you could sell the shares that you purchase in this offering. In the past, following periods of volatility in the market or significant price declines, securities class-action litigation has often been instituted against companies. Such litigation, if instituted against us, could result in substantial costs and diversion of management's attention and resources, which could materially and adversely affect our business, financial condition, results of operations and growth prospects.

If you purchase shares in this offering, you will suffer immediate dilution of your investment.

Because the public offering price per share of our common stock is higher than the net tangible book value per share of our common stock, you will suffer immediate and substantial dilution in the net tangible book value of the common stock you purchase in this offering. Investors purchasing shares of common stock in this offering will incur immediate dilution of approximately $      per share, after giving effect to this offering, assuming no sale of Pre-funded Warrants in this offering, and no exercise of the Underwriter Warrants. In addition, we have stock options and warrants outstanding. To the extent that such outstanding securities are exercised for shares of our common stock, investors purchasing our securities in this offering may experience further dilution.

There is no public market for the Pre-funded Warrants being issued by us in this offering.

There is no established public trading market for the Pre-funded Warrants, and we do not expect a market to develop. In addition, we do not intend to apply to list the Pre-funded Warrants on any securities exchange or nationally recognized trading system, including the Nasdaq Capital Market. Without an active trading market, the liquidity of the Pre-funded Warrants will be extremely limited.

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Holders of Pre-funded Warrants purchased in this offering will have no rights as shares of common stockholders until such holders exercise their Pre-funded Warrants and acquire our shares of common stock, except as otherwise provided in the Pre-funded Warrants.

Until holders of Pre-funded Warrants acquire shares of common stock upon exercise thereof, such holders will have no rights with respect to the shares of common stock underlying the Pre-funded Warrants, except to the extent that holders of the Pre-funded Warrants will have certain rights to participate in distributions or dividends paid on our shares of common stock as set forth in the Pre-funded Warrants. Upon exercise of the Pre-funded Warrants, the holders will be entitled to exercise the rights of an shares of common stockholder only as to matters for which the record date occurs after the exercise date.

You may experience significant dilution as a result of future financings and the exercise of outstanding options or warrants.

In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock, including offerings pursuant to the accompanying base prospectus. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock or other securities convertible into or exchangeable for our common stock in future transactions may be higher or lower than the price per share in this offering.

In addition, as described above in the section entitled 'The Offering,' we have a significant number of securities convertible into, or allowing the purchase of, our common stock. The exercise of outstanding options or warrants having an exercise price per share that is less than the offering price per share in this offering will increase dilution to investors in this offering. Moreover, to the extent that we issue additional options to purchase, or securities convertible into or exchangeable for, shares of our common stock in the future and those options or other securities are exercised, converted, or exchanged, stockholders may experience further dilution.

We will have broad discretion in the use of the net proceeds from this offering and may allocate the net proceeds from this offering in ways that you and other stockholders may not approve.

Our management will have broad discretion in the use of the net proceeds, including for any of the purposes described in the section entitled 'Use of Proceeds,' and you will not have the opportunity as part of your investment decision to assess whether the net proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, the ultimate use of proceeds may vary substantially from their currently intended use. The failure of our management to use these funds effectively could have a material adverse effect on our business, cause the market price of our common stock to decline, and delay the development or commercialization of our product candidates. Pending use, we may invest any net proceeds from this offering in a manner that does not produce income or loses value. Please see the section entitled 'Use of Proceeds' on page S-15 of this prospectus supplement for further information.

If we sell additional equity or debt securities to fund our operations, it may impose restrictions on our business.

In order to raise additional funds to support our operations, we may in the future sell additional equity or debt securities, which may impose restrictive covenants that adversely impact our business. The incurrence of indebtedness would result in increased fixed payment obligations and could also result in restrictive covenants, such as limitations on our ability to incur additional debt, limitations on our ability to acquire, sell or license intellectual property rights, and other operating restrictions that could adversely impact our ability to conduct our business. If we are unable to expand our operations or otherwise capitalize on our business opportunities due to such restrictions, our business, financial condition, and results of operations could be materially adversely affected.

Future sales of our common stock in the public market or other financings could cause our stock price to fall, and a substantial number of shares of common stock may be sold in the market following this offering, which may depress the market price for our common stock.

Sales of a substantial number of shares of our common stock in the public market, the perception that these sales might occur, or other financings could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. A substantial portion of the outstanding shares of our common stock are, and all of the shares sold in this offering upon issuance will be freely tradable without restriction or further registration under the Securities Act unless these shares are owned or purchased by 'affiliates' as that term is defined in Rule 144 ('Rule 144') promulgated under the Securities Act of 1933, as amended. In addition, shares of common stock issuable upon exercise of outstanding

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warrants and options, as well as shares reserved for future issuance under our incentive stock plan, will be eligible for sale in the public market to the extent permitted by applicable vesting requirements, if any, and, in some cases, subject to compliance with the requirements of Rule 144. As a result, these shares will be eligible to be freely sold in the public market upon issuance, subject to restrictions under the securities laws.

Sales of a substantial number of shares of our common stock in the public market following this offering could cause the market price of our common stock to decline. A substantial majority of the outstanding shares of our common stock are, and the shares of our common stock offered hereby will be, freely tradable without restriction or further registration under the Securities Act.

Because we do not currently intend to declare cash dividends on our shares of common stock in the foreseeable future, stockholders must rely on appreciation of the value of our common stock for any return on their investment.

We have never declared or paid cash dividends on our common stock and do not currently anticipate declaring or paying any cash dividends in the foreseeable future. In addition, the terms of any existing or future debt agreements may preclude us from paying dividends. As a result, we expect that only appreciation of the price of our common stock, if any, will provide a return to investors in this offering for the foreseeable future.

Other Risks Related to Our Business

We are relying on a third party to obtain clinical trial data of the BreathTest-1000, and the Cleveland Clinic may not perform satisfactorily, including failing to meet deadlines for the completion of such trials.

We are not independently conducting clinical trials for our product candidates and are relying on the Cleveland Clinic, to perform this function. Our reliance on this third party for clinical development activities reduces our control over these activities but does not relieve us of our regulatory responsibilities. If the Cleveland Clinic does not successfully carry out its contractual duties, meet expected deadlines or conduct our clinical trials in accordance with regulatory requirements or stated protocols, we will not be able to obtain, or may be delayed in obtaining, regulatory clearance or approval for the BreathTest-1000 and will not be able to, or may be delayed in our efforts to, successfully commercialize this product.

Clinical trials may be delayed, suspended or terminated for many reasons, which will increase our expenses and delay the time it takes to commercialize our BreathTest-1000 device.

We may experience delays in our ongoing or future preclinical studies or clinical trials, and we do not know whether future preclinical studies or clinical trials will begin on time, need to be redesigned, enroll an adequate number of patients on time or be completed on schedule, if at all. The commencement and completion of clinical trials may be delayed, suspended or terminated as a result of many factors, including:

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In particular, we are currently completing development of breath sample collection kits to capture the breath for analysis by the BreathTest-1000. There is no guarantee that we will complete design and production of breath sample collection kits for the clinical trial in partnership with the Cleveland Clinic or future clinical trials. In addition, we have experienced a delay in obtaining a component of the BreathTest-1000. We believe that our current BreathTest-1000 inventory is sufficient for the conduct of our planned clinical trial in partnership with the Cleveland Clinic, but it is possible that obtaining the component from our current supplier or alternative suppliers could take longer than expected. Although we intend to procure the component from alternative supply sources or our current supplier, we can provide no assurance that we will do so in a timely manner. Any such delays could limit our ability to meet demand for the BreathTest-1000 and delay our planned clinical trials, which would have a material adverse impact on our business, results of operations and financial condition.

We could also encounter delays if a clinical trial is suspended or terminated by us, by the IRBs or Ethics Committees of the institutions at which such trials are being conducted, by the Data Safety Monitoring Board for such trial or by the FDA or other regulatory authorities. Such authorities may suspend or terminate a clinical trial due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements, including the FDA's current Good Clinical Practice, or GCP, regulations, or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using the device, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

In addition, we may encounter delays if the FDA concludes that our financial relationships with investigators results in a perceived or actual conflict of interest that may have affected the interpretation of a study, the integrity of the data generated at the applicable clinical trial site or the utility of the clinical trial itself. Principal investigators for our clinical trials may serve as scientific advisors or consultants to us from time to time and receive cash compensation and/or stock options in connection with such services. If these relationships and any related compensation to or ownership interest by the clinical investigator carrying out the study result in perceived or actual conflicts of interest, or if the FDA concludes that the financial relationship may have affected interpretation of the study, the integrity of the data generated at the applicable clinical trial site may be questioned and the utility of the clinical trial itself may be jeopardized, which could result in the delay or rejection by the FDA. Any such delay or rejection could prevent us from commercializing the BreathTest-1000.

If we experience delays in the commencement or completion of any clinical trial of our product candidates, or if any of our clinical trials are terminated, the commercial prospects of our BreathTest-1000 therapy may be harmed, and our ability to generate revenue from sales may be delayed or materially diminished.

We do not know whether any of our future preclinical studies or clinical trials will begin as planned, will need to be restructured or will be completed on schedule, or at all. Any delays in completing our clinical trials will increase our costs, slow down our product candidate development and approval process and jeopardize our ability to commence sales and generate associated revenue. Any of these occurrences may significantly harm our business, financial condition and prospects. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial, suspension or revocation of expanded regulatory clearance or approval of our product candidates. Significant preclinical study or clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do and impair our ability to successfully commercialize the BreathTest-1000.

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DILUTION

If you invest in our common stock in this offering, your ownership interest will be immediately diluted to the extent of the difference between the offering price per share of our common stock and the as adjusted net tangible book value per share of our common stock immediately after this offering.

As of December 31, 2020, we had a historical net tangible book value of $23.6 million, or $1.27 per share of common stock. Our historical net tangible book deficit per share represents the amount of our total tangible assets less total liabilities, divided by the total number of shares of common stock outstanding at December 31, 2020.

After giving effect to this offering of       shares common stock at a public offering price of $      per share and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us, and assuming no sale of Pre-funded Warrants in this offering, our as adjusted net tangible book value per share of our common stock as of December 31, 2020 would have been approximately $      million, or $      per share of common stock. This represents an immediate increase in net tangible book value of approximately $      per share to our existing stockholders and an immediate dilution of approximately $      per share to purchasers of our common stock in this offering, as illustrated by the following table:

If the underwriter exercises its option to purchase additional shares in full, our as adjusted net tangible book value per share at December 31, 2020 after giving effect to this offering would have been $      per share, and the dilution in as adjusted net tangible book value per share to investors in this offering would have been $      per share.

The number of shares of our common stock to be outstanding after this offering as shown above is based on 24,613,330 shares outstanding as of April 6, 2021 and excludes as of that date:

To the extent that additional options or other convertible securities are issued, or outstanding options or warrants are exercised, including the Pre-funded Warrants and the warrants issued to the Underwriter in this offering, you will experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

The discussion of dilution, and the table quantifying it, assume no exercise or settlement of any outstanding equity awards, exercise of warrants, including the underwriter warrants issued as compensation to the underwriter for this offering, or other potentially dilutive securities. The exercise of potentially dilutive securities having an exercise price less than the offering price would increase the dilutive effect to new investors.

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USE OF PROCEEDS

Assuming all of the shares offered in this offering are sold, we estimate that our net proceeds from this offering will be approximately $ (or approximately $      million if the underwriter exercises in full its option to purchase up to        additional shares), after deducting underwriting discounts and commissions and estimated offering expenses payable by us and assuming no sale of Pre-funded Warrants in this offering.

We intend to use the net proceeds of this offering for general corporate purposes and working capital and capital expenditures.

As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds to be received upon the completion of this offering. The amounts and timing of its actual expenditures will depend on numerous factors, including the status of its product development efforts, sales and marketing activities, technological advances, amount of cash generated or used by its operations and competition. Accordingly, the Company's management will have broad discretion in the application of the net proceeds and investors will be relying on the judgment of its management regarding the application of the proceeds of this offering.

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DESCRIPTION OF SECURITIES OFFERED

We are offering shares of our common stock. We are also offering Pre-funded Warrants to those purchasers whose purchase of shares of common stock in this offering would result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding shares of common stock following the consummation of this offering in lieu of the shares of common stocks that would result in such excess ownership. Each Pre-funded Warrant will be exercisable for one share of common stock. No warrant for fractional shares of common stock will be issued, rather warrants will be issued only for whole shares of common stock. We are also registering the shares of common stock and the shares of common stock issuable from time to time upon exercise of the Pre-funded Warrants offered hereby.

Common Stock

The descriptions of our common stock included in the accompanying prospectus under the heading 'Description of Capital Stock' are incorporated herein by reference.

Pre-funded Warrants

The following summary of certain terms and provisions of the Pre-funded Warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by, the provisions of the Pre-funded Warrant, the form of which will be filed with the SEC as an exhibit to a Current Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement forms a part. Prospective investors should carefully review the terms and provisions of the form of Pre-funded Warrant for a complete description of the terms and conditions of the Pre-funded Warrants.

Duration and Exercise Price

Each Pre-funded Warrant offered hereby will have an initial exercise price per share of common stock equal to $0.001. The Pre-funded Warrants will be immediately exercisable and will expire when exercised in full. The exercise price and number of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of share dividends, share splits, reorganizations or similar events affecting our shares of common stock and the exercise price. Subject to the rules and regulations of the applicable trading market, we may at any time during the term of the Pre-funded Warrant, subject to the prior written consent of the holders, reduce the then current exercise price to any amount and for any period of time deemed appropriate by our board of directors.

Exercisability

The Pre-funded Warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the Pre-funded Warrant to the extent that the holder would own more than 4.99% of the outstanding shares of common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of beneficial ownership of outstanding shares after exercising the holder's Pre-funded Warrants up to 9.99% of the number of our shares of common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the Pre-funded Warrants. Purchasers of Pre-funded Warrants in this offering may also elect prior to the issuance of the Pre-funded Warrants to have the initial exercise limitation set at 9.99% of our outstanding shares of common stock.

Cashless Exercise

In lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net number of shares of common stock determined according to a formula set forth in the Pre-funded Warrants.

Fractional Shares

No fractional shares of common stock will be issued upon the exercise of the Pre-funded Warrants. Rather, the number of shares of common stock to be issued will be rounded down to the nearest whole number.

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Transferability

Subject to applicable laws, a Pre-funded Warrant may be transferred at the option of the holder upon surrender of the Pre-funded Warrant to us together with the appropriate instruments of transfer.

Trading Market

There is no trading market available for the Pre-funded Warrants on any securities exchange or nationally recognized trading system, and we do not expect a trading market to develop. We do not intend to list the Pre-funded Warrants on any securities exchange or nationally recognized trading market. Without a trading market, the liquidity of the Pre-funded Warrants will be extremely limited. The shares of common stock issuable upon exercise of the Pre-funded Warrants are currently traded on the Nasdaq Capital Market.

Right as a Shareholder

Except as otherwise provided in the Pre-funded Warrants or by virtue of such holder's ownership of shares of common stock, the holders of the Pre-funded Warrants do not have the rights or privileges of holders of our shares of common stock, including any voting rights, until they exercise their Pre-funded Warrants. The Pre-funded Warrants will provide that holders have the right to participate in distributions or dividends paid on our shares of common stock.

Fundamental Transaction

In the event of a fundamental transaction, as described in the Pre-funded Warrants and generally including any reorganization, recapitalization or reclassification of our shares of common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding shares of common stock, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding shares of common stock, the holders of the Pre-funded Warrants will be entitled to receive upon exercise of the Pre-funded Warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the Pre-funded Warrants immediately prior to such fundamental transaction.

Underwriter's Warrants

We have agreed to grant the underwriter (or its designees) warrants to purchase      shares of our common stock, which represents 6.0% of the aggregate number of shares of common stock and Pre-funded Warrants sold this offering (and warrants to purchase up to an additional      shares if the underwriter exercises its option to purchase additional shares in full), with an exercise price of $      per share. The underwriter warrants will be exercisable immediately and for five years from the commencement of the sales of this offering. The warrants issued to the underwriter and the shares of common stock issuable upon exercise of the warrants issued to the underwriter are registered on the registration statement of which this prospectus forms a part.

The following summary of certain terms and provisions of the underwriter warrants is not complete and is subject to, and qualified in its entirety by, the provisions of the underwriter warrants, the form of which will be filed with the SEC as an exhibit to a Current Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement forms a part.

Duration and Exercise Price

The exercise price and number of shares issuable upon exercise is subject to appropriate adjustment in the event of share dividends, share splits, reorganizations or similar events affecting our shares and the exercise price.

Exercisability

The underwriter warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the underwriter warrant to the extent that the holder would own more than 4.99% of the outstanding shares immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of beneficial ownership of outstanding shares after exercising the holder's underwriter warrants up to 9.99% of the number of our shares

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outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the underwriter warrants.

Cashless Exercise

If, at the time a holder exercises its underwriter warrants, a registration statement registering the issuance of the shares underlying the underwriter warrants under the Securities Act is not then effective or available for the issuance of such shares, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price and subject to the nominal value of the shares being paid up as described below, the holder may elect instead to receive upon such exercise (either in whole or in part) the net number of shares determined according to a formula set forth in the underwriter warrants.

Fractional Shares

No underwriter warrant for fractional shares will be issued, rather underwriter warrants will be issued only for whole shares. No fractional share will be issued upon the exercise of the underwriter warrants. Rather, the number of shares to be issued will be rounded down to the nearest whole number.

Transferability

Subject to applicable laws, an underwriter warrant may be transferred at the option of the holder upon surrender of the underwriter warrant to us together with the appropriate instruments of transfer.

Trading Market

There is no trading market available for the underwriter warrants on any securities exchange or nationally recognized trading system, and we do not expect a trading market to develop. We do not intend to list the underwriter warrants on any securities exchange or nationally recognized trading market. Without a trading market, the liquidity of the underwriter warrants will be extremely limited. The shares issuable upon exercise of the underwriter warrants are currently traded on the Nasdaq Capital Market.

Right as a Shareholder

Except as otherwise provided in the underwriter warrants or by virtue of such holder's ownership of shares, the holders of the underwriter warrants do not have the rights or privileges of holders of our shares, including any voting rights, until they exercise their underwriter warrants.

Fundamental Transaction

In the event of a fundamental transaction, as described in the underwriter warrants and generally including any reorganization, recapitalization or reclassification of our shares, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding shares, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding shares, the holders of the underwriter warrants will be entitled to receive upon exercise of the underwriter warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the underwriter warrants immediately prior to such fundamental transaction.

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UNDERWRITING

Pursuant to the underwriting agreement with H.C. Wainwright & Co., LLC, or the underwriter and the sole book-running manager of this offering, we have agreed to issue and sell, and the underwriter has agreed to purchase, the number of shares of common stock and Pre-funded Warrants listed opposite its name below, less the underwriting discounts and commissions, on the closing date, subject to the terms and conditions contained in the underwriting agreement. The underwriting agreement provides that the obligations of the underwriter are subject to certain customary conditions precedent, representations and warranties contained therein.

Pursuant to the underwriting agreement, the underwriter has agreed to purchase all of the shares sold under the underwriting agreement if any of these shares are purchased. The underwriter has advised us that it does not intend to confirm sales to any account over which it exercises discretionary authority.

Discounts, Commissions, and Expenses

The underwriter may offer the shares of common stock from time to time to purchasers directly or through agents, or through brokers in brokerage transactions on The Nasdaq Capital Market, or to dealers in negotiated transactions or in a combination of such methods of sale, or otherwise, at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices, subject to receipt and acceptance by it and subject to its right to reject any order in whole or in part. The difference between the price at which the underwriter purchases shares from us and the price at which the underwriter resells such shares may be deemed underwriting compensation. If the underwriter effects such transactions by selling shares of common stock to or through dealers, such dealers may receive compensation in the form of discounts, concessions, or commissions from the underwriter and/or purchasers of shares of common stock for whom they may act as agents or to whom they may sell as principal.

The underwriter is offering the shares, subject to prior sale, when, as and if issued to and accepted by it, subject to approval of legal matters and other conditions specified in the underwriting agreement. The underwriter reserves the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

We have granted to the underwriter an option to purchase up to       additional shares of common stock at the public offering price, less the underwriting discount. The option is exercisable for 30 days from the date of this prospectus supplement.

The following table shows the public offering price, underwriting discounts and commissions and proceeds, before expenses, to us. These amounts are shown assuming both no exercise and full exercise of the underwriter's option to purchase additional shares.

We have agreed to pay the legal fees and expenses of the underwriter, in the sum of up to $100,000 in connection with this offering, $50,000 for non-accountable expenses and clearing fees of $12,900. We have also agreed to pay the underwriter a management fee equal to 1.0% of the aggregate gross proceeds in this offering. We estimate that the total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $      and are payable by us.

Additionally, we agreed to grant the underwriter (or its designees) warrants to purchase      shares of our common stock, which represents 6.0% of the aggregate number of shares of common stock and Pre-funded Warrants sold this offering (and warrants to purchase up to an additional      shares if the underwriter exercises its option to purchase additional shares in full), with an exercise price of $      per share (representing 125% of the public offering price per share). The underwriter warrants will be exercisable immediately and for five years from the commencement of the sales of this offering. The warrants issued to the underwriter and the shares of common stock issuable upon exercise of the warrants issued to the underwriter are registered on the registration statement of which this prospectus forms a part.

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Tail

In the event that any investors that were contacted about this offering or were introduced to us in connection with this offering by the underwriter provide any capital to us in a public or private offering or capital-raising transaction within twelve months following the date of the expiration or termination of our engagement of the underwriter, we shall pay the underwriter certain cash and warrant compensation on the gross proceeds from such investors.

Indemnification

We have agreed to indemnify the underwriter against certain liabilities, including civil liabilities under the Securities Act, or to contribute to payments that the underwriter may be required to make in respect of those liabilities.

Lock-Up Agreements

We and our officers and directors have agreed to not sell any shares of our common stock or any securities convertible into or exercisable or exchangeable into share of common stock, subject to certain exceptions, for a period of 90 days after the date of closing of the offering pursuant to this prospectus supplement unless we or our officers and directors obtain prior written consent of the underwriter. This consent may be given at any time without public notice, and the underwriter may consent in its sole discretion. The exceptions to the restriction include, among other things, the issuance of any shares of our capital stock or securities convertible into shares of our capital stock that are issued (i) pursuant to a stock or option plan, (ii) pursuant to the exercise or exchange of or conversion of any securities exercisable or exchangeable for or convertible into shares of common stock issued and outstanding on the date of this prospectus supplement, provided that such securities are not amended after the date of this prospectus supplement, (iii) as consideration in an acquisition, merger or similar strategic transaction approved by a majority of the disinterested directors, provided that such securities are issued as 'restricted securities' as defined in Rule 144 and carry no registration rights that require or permit the filing of any registration statement in connection therewith within 90 days after the date of this prospectus supplement, and provided that any such issuance shall only be to a person providing us business synergies and additional benefits in addition to the investment of funds, but shall not include a transaction in which we are issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities. In addition, subject to an exception for an 'at the market' offering, after 90 days following the date of closing of this offering, we have agreed to not issue any securities that are subject to a price reset based on the trading prices of our common stock or upon a specified or contingent event in the future, or enter into any agreement to issue securities at a future determined price, for one year following the date of closing of this offering, which prohibition may be waived at any time without public notice by the underwriter.

Price Stabilization, Short Positions, and Penalty Bids

In connection with this offering, the underwriter may engage in stabilizing transactions, overallotment transactions, syndicate covering transactions and penalty bids in connection with our common stock.

Stabilizing transactions permit bids to purchase shares of common stock so long as the stabilizing bids do not exceed a specified maximum.

Overallotment transactions involve sales by the underwriter of common shares in excess of the number of shares the underwriter is obligated to purchase. This creates a syndicate short position which may be either a covered short position or a naked short position. In a covered short position, the number of shares over-allotted by the underwriter is not greater than the number of shares that it may purchase in the overallotment option. In a naked short position, the number of shares involved is greater than the number of shares in the overallotment option. The underwriter may close out any short position by exercising its overallotment option and/or purchasing shares in the open market.

Syndicate covering transactions involve purchases of common stock in the open market after the distribution has been completed in order to cover syndicate short positions. Such a naked short position would be closed out by buying securities in the open market. A naked short position is more likely to be created if the underwriter is concerned that there could be downward pressure on the price of the securities in the open market after pricing that could adversely affect investors who purchase in the offering.

Penalty bids permit the underwriter to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a stabilizing or syndicate covering transaction to cover syndicate short positions.

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These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock in the open market may be higher than it would otherwise be in the absence of these transactions. Neither we nor the underwriter makes any representation or prediction as to the effect that the transactions described above may have on the price of our common stock. These transactions may be effected on The Nasdaq Capital Market, in the over-the-counter market or otherwise and, if commenced, may be discontinued at any time.

In connection with this offering, the underwriter also may engage in passive market making transactions in our common stock in accordance with Regulation M during a period before the commencement of offers or sales of shares of our common stock in this offering and extending through the completion of the distribution. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for that security. However, if all independent bids are lowered below the passive market maker's bid that bid must then be lowered when specific purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

Electronic Distribution

A prospectus in electronic format may be made available on the websites maintained by the underwriter, if any, participating in this offering and the underwriter may distribute prospectuses electronically. Other than the prospectus in electronic format, the information on these websites is not part of this prospectus or the registration statement of which this prospectus forms a part, has not been approved or endorsed by us or the underwriter, and should not be relied upon by investors.

Other Relationships

From time to time, the underwriter and its affiliates have provided, and may provide in the future, various advisory, investment and commercial banking and other services to us in the ordinary course of business, for which it has received and may continue to receive customary fees and commissions. In particular, the underwriter acted as our placement agent in connection with our registered direct offerings consummated in March 2020, October 2020, and February 2021, a public offering we consummated on October 23, 2020, as well as our sales agent for the ATM Offering, for which it received compensation.

Transfer Agent and Registrar

The Transfer Agent and Registrar for our common stock is American Stock Transfer & Trust Company, LLC. The transfer agent's address is 6201 15^th Avenue, Brooklyn, New York 11219.

NASDAQ Capital Market Listing

Our stock is currently traded on the Nasdaq Capital Market under the symbol 'ASTC'. On April 6, 2021, the last reported sale price of our common stock was $2.18 per share. We do not plan to list the Pre-funded Warrants or the Placement Agent's Warrants on the Nasdaq Capital Market or any other securities exchange or trading market.

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LEGAL MATTERS

The validity of the shares of common stock offered hereby will be passed upon for us by Sheppard, Mullin, Richter & Hampton LLP, New York, New York. Ellenoff Grossman & Schole LLP, New York, New York is acting as counsel to the underwriter in connection with this offering.

EXPERTS

Armanino LLP, an independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended June 30, 2020, as set forth in their report, which includes an explanatory paragraph as to the Company's ability to continue as a going concern, dated September 8, 2020, which is incorporated by reference in this prospectus supplement and elsewhere in the registration statement. Our consolidated financial statements are incorporated by reference in reliance on Armanino LLP's report, given on the authority of such firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC, which are available at the SEC's website at http://www.sec.gov. In addition, we maintain a website that contains information about us at http://www.astrotechcorp.com. The information found on, or otherwise accessible through, our website is not incorporated into, and does not form a part of, this prospectus supplement or any other report or document we file with or furnish to the SEC.

We have filed with the SEC a registration statement on Form S-3 (File No. 333-253835) under the Securities Act with respect to the shares of common stock offered by this prospectus supplement. When used in this prospectus supplement, the term 'registration statement' includes amendments to the registration statement as well as the exhibits, schedules, financial statements and notes filed as part of the registration statement or incorporated by reference therein. This prospectus supplement, which constitutes a part of the registration statement, omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information on us and our consolidated subsidiaries and the common stock we are offering by this prospectus supplement. Statements herein concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements. You can obtain a copy of the registration statement from the SEC at the address listed above or from the SEC's website.

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INCORPORATION OF DOCUMENTS BY REFERENCE

This prospectus supplement is part of the registration statement but the registration statement includes and incorporates by reference additional information and exhibits. The SEC permits us to 'incorporate by reference' the information contained in documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents rather than by including them in this prospectus supplement. Information that is incorporated by reference is considered to be part of this prospectus supplement and you should read it with the same care that you read this prospectus supplement. Information that we file later with the SEC will automatically update and supersede the information that is either contained, or incorporated by reference, in this prospectus supplement, and will be considered to be a part of this prospectus supplement from the date those documents are filed. We have filed with the SEC, and incorporate by reference in this prospectus supplement:

In addition, all documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, prior to the termination of the offering (excluding any information furnished rather than filed) shall be deemed to be incorporated by reference into this prospectus supplement.

Notwithstanding the statements in the preceding paragraphs, no document, report or exhibit (or portion of any of the foregoing) or any other information that we have 'furnished' to the SEC pursuant to the Securities Exchange Act of 1934, as amended shall be incorporated by reference into this prospectus supplement.

We will furnish without charge to you, on written or oral request, a copy of any or all of the documents incorporated by reference in this prospectus supplement, including exhibits to these documents. You should direct any requests for documents to:

Astrotech Corporation

2028 E. Ben White Blvd. #240-9530

Austin, Texas 78741

Phone: (512) 485-9530

You also may access these filings on our website at http://www.astrotechcorp.com. We do not incorporate the information on our website into this prospectus supplement or any supplement to this prospectus and you should not consider any information on, or that can be accessed through, our website as part of this prospectus supplement or any supplement to this prospectus (other than those filings with the SEC that we specifically incorporate by reference into this prospectus supplement or any supplement to this prospectus).

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus supplement will be deemed modified, superseded or replaced for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement modifies, supersedes or replaces such statement. Any statement contained herein or in any document incorporated or deemed to be incorporated by reference shall be deemed to be modified or superseded for purposes of the registration statement of which this prospectus supplement forms a part to the extent that a statement contained in any other subsequently filed document which also is or is deemed to be incorporated by reference modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed to constitute a part of the registration statement of which this prospectus supplement forms a part, except as so modified or superseded.

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PROSPECTUS

ASTROTECH CORPORATION

$250,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

We may offer and sell, from time to time in one or more offerings, any combination of common stock, preferred stock, debt securities, warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities, having an aggregate initial offering price not exceeding $250,000,000.

This prospectus provides a general description of the securities we may offer. Each time we sell a particular class or series of securities, we will provide specific terms of the securities offered in a supplement to this prospectus. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. You should read carefully this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference herein or therein before you invest in any of our securities.

This prospectus may not be used to offer or sell our securities unless accompanied by a prospectus supplement relating to the offered securities.

Our common stock is presently listed on the NASDAQ Capital Market under the symbol 'ASTC'. On March 02, 2021, the last reported sale price of our common stock was $2.44. The applicable prospectus supplement will contain information, where applicable, as to any other listing on the NASDAQ Capital Market or any securities market or other exchange of the securities, if any, covered by the prospectus supplement.

These securities may be sold directly by us, through dealers or agents designated from time to time, to or through underwriters, dealers or through a combination of these methods on a continuous or delayed basis. See 'Plan of Distribution' in this prospectus. We may also describe the plan of distribution for any particular offering of our securities in a prospectus supplement. If any agents, underwriters or dealers are involved in the sale of any securities in respect of which this prospectus is being delivered, we will disclose their names and the nature of our arrangements with them in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from any such sale will also be included in a prospectus supplement.

Investing in our securities involves various risks. See 'Risk Factors' contained herein for more information on these risks. Additional risks will be described in the related prospectus supplements under the heading 'Risk Factors'. You should review that section of the related prospectus supplements for a discussion of matters that investors in our securities should consider.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the adequacy or accuracy of this prospectus or any accompanying prospectus supplement. Any representation to the contrary is a criminal offense.

The date of this Prospectus is March 15, 2021.

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TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission (the 'SEC') under the Securities Act of 1933, as amended (the 'Securities Act') using a 'shelf' registration process. Under this shelf registration process, we may from time to time sell common stock, preferred stock, debt securities or warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities, in one or more offerings up to a total dollar amount of $250,000,000. We have provided to you in this prospectus a general description of the securities we may offer. Each time we sell securities under this shelf registration, we will, to the extent required by law, provide a prospectus supplement that will contain specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in any documents that we have incorporated by reference into this prospectus. To the extent there is a conflict between the information contained in this prospectus and the prospectus supplement or any related free writing prospectus, you should rely on the information in the prospectus supplement or the related free writing prospectus; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date - for example, a document incorporated by reference in this prospectus or any prospectus supplement or any related free writing prospectus - the statement in the document having the later date modifies or supersedes the earlier statement.

We have not authorized any dealer, agent or other person to give any information or to make any representation other than those contained or incorporated by reference in this prospectus, any accompanying prospectus supplement or any related free writing prospectus that we may authorize to be provided to you. You must not rely upon any information or representation not contained or incorporated by reference in this prospectus or an accompanying prospectus supplement, or any related free writing prospectus that we may authorize to be provided to you. This prospectus, the accompanying prospectus supplement and any related free writing prospectus, if any, do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor do this prospectus, the accompanying prospectus supplement or any related free writing prospectus, if any, constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction. You should not assume that the information contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference (as our business, financial condition, results of operations and prospects may have changed since that date), even though this prospectus, any applicable prospectus supplement or any related free writing prospectus is delivered or securities are sold on a later date.

As permitted by the rules and regulations of the SEC, the registration statement, of which this prospectus forms a part, includes additional information not contained in this prospectus. You may read the registration statement and the other reports we file with the SEC at the SEC's web site or at the SEC's offices described below under the heading 'Where You Can Find Additional Information.'

Company References

In this prospectus, 'Astrotech,' 'the Company,' 'we,' 'us,' and 'our' refer to Astrotech Corporation, a Delaware corporation, unless the context otherwise requires.

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OUR BUSINESS

Astrotech Corporation (Nasdaq: ASTC) ('Astrotech,' the 'Company,' 'we,' 'us,' or 'our'), a Delaware corporation organized in 1984, is a science and technology development and commercialization company that launches, manages, and builds scalable companies based on innovative technology in order to maximize shareholder value.

Our efforts are focused on commercializing its platform mass spectrometry technology through its wholly-owned subsidiaries:

Our Business Units

Astrotech Technologies, Inc.

ATI owns and licenses the AMS Technology, the platform mass spectrometry technology originally developed by 1^st Detect. The intellectual property includes 32 granted patents and two additional patents in process along with extensive trade secrets. With a number of diverse market opportunities for the core technology, ATI is structured to license the intellectual property for different fields of use. ATI currently licenses the AMS Technology to three wholly-owned subsidiaries of Astrotech, including to 1^st Detect for use in the security and detection market, to AgLAB for use in the agriculture market, and to BreathTech for use in breath analysis.

1^st Detect Corporation

1^st Detect, an exclusive licensee of ATI for the security and detection market, has developed the TRACER 1000™, the world's first mass spectrometer ('MS') based explosives trace detector ('ETD') certified by the European Civil Aviation Conference ('ECAC'), designed to replace the ETDs used at airports, cargo facilities, secured facilities, and borders worldwide. We believe that ETD customers are unsatisfied with the currently deployed ETD technology, which is driven by ion mobility spectrometry ('IMS'). We believe that IMS-based ETDs are fraught with false positives, as they often misidentify personal care products and other common household chemicals as explosives, causing unnecessary delays, frustration, and significant wasted security resources. In addition, there are hundreds of different types of explosives, but IMS-based ETDs have a very limited threat detection library reserved only for those several explosives of largest concern. Adding additional compounds to the detection library of an IMS-based ETD fundamentally reduces the instrument's performance, further increasing the likelihood of false alarms. In contrast, adding additional compounds does not degrade the TRACER 1000's detection capabilities, as it has a virtually unlimited and easily expandable threat library. With terrorist threats becoming more numerous, sophisticated, and lethal, security professionals have been looking for better instrumentation, and specifically for mass spectrometry, to address the evolving threats, but mass spectrometry has long been too expensive, too cumbersome, and not practical for security applications until the launch of the TRACER 1000.

In order to sell the TRACER 1000 to airport and cargo security customers in the European Union, ECAC certification is required. Certain other countries also accept ECAC certification. After receiving ECAC certification for the TRACER 1000 on February 21, 2019, we are now marketing to and taking orders from airports and cargo facilities outside of the U.S. that accept ECAC certification.

On June 26, 2019, the Company announced the official launch of the TRACER 1000, and on November 22, 2019, we announced our first commercial sale of TRACER 1000 units to a global shipping and logistics company.

In the United States, we are working with the TSA towards Air Cargo certification. On March 27, 2018, we announced that the TRACER 1000 was accepted into TSA's Air Cargo Screening Technology Qualification Test ('ACSQT') and, on April 4, 2018, we announced that the TRACER 1000 was beginning testing with TSA for passenger screening at airports. On November 14, 2019, we announced that the TRACER 1000 had been selected by the TSA's Innovation Task Force to conduct live checkpoint screening at Miami International Airport. With similar protocols as ECAC testing, we have received valuable feedback from all programs. Following ECAC certification and acceptance in the cargo market, testing for cargo security continued with the TSA. With the COVID-19 pandemic, all testing within

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the TSA was put on hold; however, cargo non-detection testing resumed during the summer of 2020, and we subsequently announced on September 9, 2020 that the TRACER 1000 passed the non-detection testing portion of the TSA's ACSQT. TSA cargo detection testing resumed during the fall of 2020 and continues to move forward. This is the next and final step to be listed on the Air Cargo Screening Technology List ('ACSTL') as an 'approved' device and, if approved, thereby approved for cargo sales in the United States. Given the deterioration in air traffic caused by the pandemic, we have determined to put TSA certification testing for passenger checkpoint security on indefinite hold.

Finally, on October 28, 2020, the Company announced that it had surpassed $1.0 million in purchase orders for the TRACER 1000 and an additional $1.0 million in future service and support commitments, also announcing DHL (Deutsche Post AG) as its largest flagship customer.

AgLAB Inc.

AgLAB, an exclusive licensee of ATI for the agriculture market, has developed the AgLAB-1000™ series of mass spectrometers for process control and in the detection of trace levels of solvents and pesticides. The AgLAB product line is a derivative of our core AMS Technology. The AMS Technology provides a significant competitive advantage due to its small size, rugged design, quick analysis, ease of use, and affordability. These attributes are valuable for agriculture applications in both processing facilities and in the field.

BreathTech Corporation

BreathTech, an exclusive licensee of ATI for breath analysis, is developing the BreathTest-1000™, a breath analysis tool to screen for VOC metabolites found in a person's breath that could indicate they may have an infection, including COVID-19 or pneumonia.

Development of the BreathTest-1000 follows our positive results in pre-clinical trials for the BreathDetect-1000™, a rapid self-serve breathalyzer that detects bacterial infections in the respiratory tract, including pneumonia. The pre-clinical trials were conducted in collaboration with UT Health San Antonio in 2017.

On October 20, 2020, we announced a joint development agreement with The Cleveland Clinic Foundation to explore leveraging the BreathTest-1000 to rapidly screen for COVID-19 or related indicators. The goal of the agreement is to develop a non-invasive device that will use breath samples to identify COVID-19 strains, with the potential to provide a low-cost, self-service screening option that could be deployed on a large-scale.

The Securities We May Offer

We may offer shares of our common stock and preferred stock, various series of debt securities and warrants to purchase any of such securities, either individually or in units, with a total value of up to $250,000,000 from time to time under this prospectus, together with any applicable prospectus supplement and related free writing prospectus, at prices and on terms to be determined by market conditions at the time of offering. If we issue any debt securities at a discount from their original stated principal amount, then, for purposes of calculating the total dollar amount of all securities issued under this prospectus, we will treat the initial offering price of the debt securities as the total original principal amount of the debt securities. Each time we offer securities under this prospectus, we will provide offerees with a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities being offered, including, to the extent applicable:

Common Stock

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A prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in documents we have incorporated by reference. However, no prospectus supplement or free writing prospectus will offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

We may sell the securities to or through underwriters, dealers or agents or directly to purchasers. We, as well as any agents acting on our behalf, reserve the sole right to accept and to reject in whole or in part any proposed purchase of securities. Each prospectus supplement will set forth the names of any underwriters, dealers or agents involved in the sale of securities described in that prospectus supplement and any applicable fee, commission or discount arrangements with them, details regarding any over-allotment option granted to them, and net proceeds to us. The following is a summary of the securities we may offer with this prospectus.

We currently have authorized 50,000,000 shares of common stock, $0.001 par value. We may offer shares of our common stock either alone or underlying other registered securities convertible into or exercisable for our common stock. Holders of our common stock are entitled to such dividends as our Board of Directors (the 'Board' or 'Board of Directors') may declare from time to time out of legally available funds, subject to the preferential rights of the holders of any shares of our preferred stock that are outstanding or that we may issue in the future. Currently, we do not pay any dividends on our common stock. Each holder of our common stock is entitled to one vote per share. In this prospectus, we provide a general description of, among other things, the rights and restrictions that apply to holders of our common stock.

Preferred Stock

We currently have authorized 2,500,000 shares of preferred stock, $0.001 par value. Our Board has designated 300,000 as Series A Junior Preferred Stock, none of which are outstanding. The Board has also designated Series C and Series D Preferred Stock, of which no shares and 280,898 shares are outstanding, respectively, as of June 30, 2020. Any authorized and undesignated shares of preferred stock may be issued from time to time in one or more series pursuant to a resolution or resolutions providing for such issue duly adopted by our Board of Directors (authority to do so being hereby expressly vested in the Board of Directors). The Board of Directors is further authorized, subject to limitations prescribed by law, to fix by resolution or resolutions the designations, powers, preferences and rights, and the qualifications, limitations or restrictions thereof, of any wholly unissued series of preferred stock, including without limitation authority to fix by resolution or resolutions the dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions), redemption price or prices, and liquidation preferences of any such series, and the number of shares constituting any such series and the designation thereof, or any of the foregoing.

The rights, preferences, privileges and restrictions granted to or imposed upon any series of preferred stock that we offer and sell under this prospectus and applicable prospectus supplements will be set forth in a certificate of designation relating to the series. We will incorporate by reference into the registration statement of which this prospectus is a part the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of shares of that series of preferred stock. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of preferred stock being offered, as well as the complete certificate of designation that contains the terms of the applicable series of preferred stock.

Debt Securities

We may offer general debt obligations, which may be secured or unsecured, senior or subordinated and convertible into shares of our common stock. In this prospectus, we refer to the senior debt securities and the subordinated debt securities together as the 'debt securities.' We may issue debt securities under a note purchase agreement or under an indenture to be entered between us and a trustee. Forms of the senior and subordinated indentures are included as an exhibit to the registration statement of which this prospectus is a part. The indentures do not limit the amount of securities that may be issued under it and provides that debt securities may be issued in one or more series. The senior debt securities will have the same rank as all of our other indebtedness that is not subordinated. The subordinated debt securities will be subordinated to our senior debt on terms set forth in the applicable prospectus supplement. In addition, the subordinated debt securities will be effectively subordinated to creditors and preferred shareholders of our subsidiaries. Our Board of Directors will determine the terms of each series of debt securities being offered. This prospectus contains only general terms and provisions of the debt securities. The applicable prospectus supplement will describe the particular terms of the debt securities offered thereby. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of debt securities being offered, as well as the complete note agreements and/or indentures that contain the terms of the debt securities. Forms of indentures have been filed as exhibits to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of debt securities being offered will be incorporated by reference into the registration statement of which this prospectus is a part from reports we file with the SEC.

Warrants

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We may offer warrants for the purchase of shares of our common stock or preferred stock or of debt securities. We may issue the warrants by themselves or together with common stock, preferred stock or debt securities, and the warrants may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and the investors or a warrant agent. Our Board of Directors will determine the terms of the warrants. This prospectus contains only general terms and provisions of the warrants. The applicable prospectus supplement will describe the particular terms of the warrants being offered thereby. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of warrants being offered, as well as the complete warrant agreements that contain the terms of the warrants. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference into the registration statement of which this prospectus is a part from reports we file with the SEC.

Units

We may offer units consisting of our common stock or preferred stock, debt securities and/or warrants to purchase any of these securities in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. Each unit agent will be a bank or trust company that we select. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units. This prospectus contains only a summary of certain general features of the units. The applicable prospectus supplement will describe the particular features of the units being offered thereby. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of units being offered, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions and will be incorporated by reference into the registration statement of which this prospectus is a part from reports we file with the SEC.

Corporate Information

Our principal executive offices are located at 2028 E. Ben White Blvd., Suite 240-9530, Austin, Texas 78741. Our telephone number is (512) 485-9530 and our website address is www.astrotechcorp.com. The information on our website is not a part of, and should not be construed as being incorporated by reference into, this prospectus or any prospectus supplement.

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RISK FACTORS

An investment in our securities involves a high degree of risk. This prospectus contains, and the prospectus supplement applicable to each offering of our securities will contain, a discussion of the risks applicable to an investment in our securities. Prior to making a decision about investing in our securities, you should carefully consider the specific factors discussed under the heading 'Risk Factors' in this prospectus and the applicable prospectus supplement, together with all of the other information contained or incorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under Item 1A, 'Risk Factors,' in our Annual Report on Form 10-K for the fiscal year ended June 30, 2020, filed with the SEC on November 8, 2020, and any updates described in our Quarterly Reports on Form 10-Q, all of which are incorporated herein by reference, and may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future and any prospectus supplement related to a particular offering. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. The occurrence of any of these known or unknown risks might cause you to lose all or part of your investment in the offered securities.

FORWARD-LOOKING STATEMENTS

This prospectus and any accompanying prospectus supplement, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the 'Securities Act') and Section 21E of the Securities Exchange Act of 1934, as amended (the 'Exchange Act'). Any statements in this prospectus and any accompanying prospectus supplement about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and are forward-looking statements. These statements are often, but not always, made through the use of words or phrases such as 'believe,' 'will,' 'expect,' 'anticipate,' 'estimate,' 'intend,' 'plan' and 'would.' For example, statements concerning financial condition, possible or assumed future results of operations, growth opportunities, industry ranking, plans and objectives of management, markets for our common stock and future management and organizational structure are all forward-looking statements. Forward-looking statements are not guarantees of performance. They involve known and unknown risks, uncertainties and assumptions that may cause actual results, levels of activity, performance or achievements to differ materially from any results, levels of activity, performance or achievements expressed or implied by any forward-looking statement.

Any forward-looking statements are qualified in their entirety by reference to the risk factors discussed throughout this prospectus and any accompanying prospectus supplement. Some of the risks, uncertainties and assumptions that could cause actual results to differ materially from estimates or projections contained in the forward-looking statements include but are not limited to:

The foregoing list sets forth some, but not all, of the factors that could affect our ability to achieve results described in any forward-looking statements. You should read this prospectus and any accompanying prospectus supplement and the documents that we reference herein and therein and have filed as exhibits to the registration statement, of which this prospectus is part, completely and with the understanding that our actual future results may be materially different from what we expect. You should assume that the information appearing in this prospectus and any accompanying prospectus supplement is accurate as of the date on the front cover of this prospectus or such prospectus supplement only. Because the risk factors referred to on page of this prospectus and incorporated herein by reference, could cause actual results or outcomes to differ materially from those expressed in any forward-looking statements made by us or on our behalf, you should not place undue reliance on any forward-looking statements. Further, any forward-looking statement speaks only as of the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge

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from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. We qualify all of the information presented in this prospectus and any accompanying prospectus supplement, and particularly our forward-looking statements, by these cautionary statements.

USE OF PROCEEDS

Except as described in any prospectus supplement and any free writing prospectus in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered under this prospectus for general corporate purposes and working capital and capital expenditures. We may also use the net proceeds to invest in or acquire complementary businesses, products or technologies, develop joint ventures, or engage in other strategic investments, although we have no current commitments or agreements with respect to any such investments or acquisitions as of the date of this prospectus. We have not determined the amount of net proceeds to be used specifically for the foregoing purposes. As a result, our management will have broad discretion in the allocation of the net proceeds and investors will be relying on the judgment of our management regarding the application of the proceeds of any sale of the securities. Pending use of the net proceeds, we may invest the proceeds in short-term, investment-grade, interest-bearing instruments, or other similar investment vehicles.

Each time we offer securities under this prospectus, we will describe the intended use of the net proceeds from that offering in the applicable prospectus supplement. The actual amount of net proceeds we spend on a particular use will depend on many factors, including, our future capital expenditures, the amount of cash required by our operations, and our future revenue growth, if any. Therefore, we will retain broad discretion in the use of the net proceeds.

THE SECURITIES WE MAY OFFER

We may offer shares of common stock, shares of preferred stock, debt securities or warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities. We may offer up to $250,000,000 of securities under this prospectus. If securities are offered as units, we will describe the terms of the units in a prospectus supplement.

DESCRIPTION OF CAPITAL STOCK

General

The following description of our capital stock, together with any additional information we include in any applicable prospectus supplement or any related free writing prospectus, summarizes the material terms and provisions of our common stock and the preferred stock that we may offer under this prospectus. While the terms we have summarized below will apply generally to any future common stock or preferred stock that we may offer, we will describe the particular terms of any class or series of these securities in more detail in the applicable prospectus supplement. For the complete terms of our common stock and preferred stock, please refer to our Certificate of Incorporation and our Bylaws ('Bylaws') that are incorporated by reference into the registration statement of which this prospectus is a part or may be incorporated by reference in this prospectus or any applicable prospectus supplement. The terms of these securities may also be affected by the Delaware General Corporation Law (the 'DGCL'). The summary below and that contained in any applicable prospectus supplement or any related free writing prospectus are qualified in their entirety by reference to our Certificate of Incorporation and our Bylaws.

As of the date of this prospectus, our authorized capital stock consisted of 50,000,000 shares of common stock, $0.001 par value, and 2,500,000 shares of preferred stock, $0.001 par value. Our Board may establish the rights and preferences of the preferred stock from time to time. As of February 22, 2021, there were 22,977,059 shares of our common stock issued and 22,577,135 outstanding and 280,898 shares of preferred stock issued and outstanding.

Common Stock

Holders of our common stock are entitled to one vote per share. Our Certificate of Incorporation does not provide for cumulative voting. Holders of our common stock are entitled to receive ratably such dividends, if any, as may be declared by our Board out of legally available funds. However, the current policy of our Board is to retain earnings, if any, for the operation and expansion of our Company. Upon liquidation, dissolution or winding-up, the holders of our common stock are entitled to share ratably in all of our assets which are legally available for distribution, after payment of or provision for all liabilities. The holders of our common stock have no preemptive, subscription, redemption or conversion rights.

Preferred Stock

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Our Articles of Incorporation provides that our Board may by resolution, without further vote or action by the shareholders, establish one or more classes or series of preferred stock having the number of shares and relative voting rights, designation, dividend rates, liquidation, and other rights, preferences, and limitations as may be fixed by them without further shareholder approval. Once designated by our Board, each series of preferred stock will have specific financial and other terms that will be described in a prospectus supplement. The description of the preferred stock that is set forth in any prospectus supplement is not complete without reference to the documents that govern the preferred stock. These include our Certificate of Incorporation and any certificates of designation that the Board may adopt. Prior to the issuance of shares of each series of preferred stock, the Board is required to adopt resolutions and file a certificate of designation with the Secretary of State of the State of Delaware. The certificate of designation fixes for each class or series the designations, powers, preferences, rights, qualifications, limitations and restrictions, including, but not limited to, some or all of the following:

The issuance of preferred stock may delay, deter or prevent a change in control.

The description of preferred stock above and the description of the terms of a particular series of preferred stock in any applicable prospectus supplement are not complete. You should refer to any applicable certificate of designation for complete information.

All shares of preferred stock offered hereby will, when issued, be fully paid and nonassessable, including shares of preferred stock issued upon the exercise of preferred stock warrants or subscription rights, if any.

Anti-Takeover Effects of Certain Provisions of our Articles of Incorporation, Bylaws and the Delaware General Corporation Law

We are governed by the provisions of Section 203 of the DGCL. In general, Section 203 prohibits a publicly traded Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is approved in a prescribed manner. A business combination includes mergers, asset sales or other transactions resulting in a financial benefit to the stockholder. An interested stockholder is a person who, together with affiliates and associates, owns (or within three years, did own) 15% or more of the corporation's voting stock, subject to certain exceptions. The statute could have the effect of delaying, deferring or preventing a change in control of our company.

Furthermore, our Certificate of Incorporation and Bylaws may have the effect of discouraging potential acquisition proposals or making a tender offer or delaying or preventing a change in control, including changes a shareholder might consider favorable. Such provisions may also prevent or frustrate attempts by our shareholders to replace or remove our management. In particular, the Certificate of Incorporation and Bylaws, as applicable, among other things:

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These provisions are expected to discourage certain types of coercive takeover practices and inadequate takeover bids and to encourage persons seeking to acquire control of us to first negotiate with its Board. These provisions may delay or prevent someone from acquiring or merging with us, which may cause our market price of our common stock to decline.

Blank Check Preferred. Our Board is authorized to create and issue from time to time, without shareholder approval, up to an aggregate of 2,500,000 shares of preferred stock in one or more series and to establish the number of shares of any series of preferred stock and to fix the designations, powers, preferences and rights of the shares of each series and any qualifications, limitations or restrictions of the shares of each series. The authority to designate preferred stock may be used to issue series of preferred stock, or rights to acquire preferred stock, that could dilute the interest of, or impair the voting power of, holders of the common stock or could also be used as a method of determining, delaying or preventing a change of control. Our Board has designated 300,000 as Series A Junior Preferred Stock.

Advance Notice Bylaws. The Bylaws contain an advance notice procedure for shareholder proposals to be brought before any meeting of shareholders, including proposed nominations of persons for election to our Board. Shareholders at any meeting will only be able to consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our Board or by a shareholder who was a shareholder of record on the record date for the meeting, who is entitled to vote at the meeting and who has given our corporate secretary timely written notice, in proper form, of the shareholder's intention to bring that business before the meeting. The Bylaws may have the effect of precluding the conduct of certain business at a meeting if the proper procedures are not followed or may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect its own slate of directors or otherwise attempting to obtain control of us.

Limitations on Liability, Indemnification of Officers and Directors and Insurance

Our Certificate of Incorporation contains provisions that limit the liability of our current and former directors for monetary damages to the fullest extent permitted by the DGCL. The DGCL provides that directors of a corporation will not be personally liable for monetary damages for any breach of fiduciary duties as directors, except liability for:

This limitation of liability does not apply to liabilities arising under federal securities laws and does not affect the availability of equitable remedies such as injunctive relief or rescission.

Our Certificate of Incorporation provides that we are authorized to indemnify our directors and officers to the fullest extent permitted by the DGCL. Our Bylaws provide that we are required to indemnify our directors and executive officers to the fullest extent permitted by the DGCL. Our Bylaws require that, upon satisfaction of certain conditions, we are required to advance expenses incurred by a director or executive officer in advance of the final disposition of any action or proceeding, and permit us to secure insurance on behalf of any officer, director, employee or other agent for any liability arising out of his or her actions in that capacity regardless of whether we would otherwise be permitted to indemnify him or her under the provisions of the DGCL. Our amended and restated bylaws will also provide our board of directors with discretion to indemnify our other officers and employees when determined appropriate by our board of directors. We have entered and expect to continue to enter into agreements to indemnify our directors, executive officers and other employees as determined by the board of directors. With certain exceptions, these agreements provide for indemnification for related expenses, including, among other things, attorneys' fees, judgments, fines and settlement amounts incurred by any of these individuals in any action or proceeding. We believe that these provisions and agreements are necessary to attract and retain qualified persons as directors and officers. We also maintain customary directors' and officers' liability insurance.

The limitation of liability and indemnification provisions in our Certificate of Incorporation and Bylaws may discourage stockholders from bringing a lawsuit against our directors for breach of their fiduciary duty. They may also reduce the likelihood of derivative litigation against our directors and officers, even though an action, if successful, might benefit us and other stockholders. Further, a stockholder's investment may be adversely affected to the extent that we pay the costs of settlement and damage awards against directors and officers as required by these indemnification provisions. At present, there is no pending litigation or proceeding involving any of our directors, officers or employees for which indemnification is sought, and we are not aware of any threatened litigation that may result in claims for indemnification.

Authorized but Unissued Shares

Our authorized but unissued shares of common stock and preferred stock will be available for future issuance without your approval. We may use additional shares for a variety of purposes, including future public offerings to raise additional capital, to fund acquisitions

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and as employee compensation. The existence of authorized but unissued shares of common stock and preferred stock could render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

Transfer Agent and Registrar

The Transfer Agent and Registrar for our common stock is American Stock Transfer & Trust Company, LLC.

DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplements or free writing prospectuses, summarizes the material terms and provisions of the debt securities that we may offer under this prospectus. We may issue debt securities, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any future debt securities we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement or free writing prospectus. The terms of any debt securities we offer under a prospectus supplement may differ from the terms we describe below. However, no prospectus supplement shall fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness. As of the date of this prospectus, we have no outstanding registered debt securities. Unless the context requires otherwise, whenever we refer to the 'indentures,' we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue any senior debt securities under the senior indenture that we will enter into with the trustee named in the senior indenture. We will issue any subordinated debt securities under the subordinated indenture and any supplemental indentures that we will enter into with the trustee named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement, of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

The indentures will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We use the term 'trustee' to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualified in their entirety by reference to, all of the provisions of the indenture and any supplemental indentures applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indentures that contains the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our Board of Directors and set forth or determined in the manner provided in an officers' certificate or by a supplemental indenture. Debt securities may be issued in separate series without limitation as to aggregate principal amount. We may specify a maximum aggregate principal amount for the debt securities of any series. We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

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Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement the terms under which a series of debt securities may be convertible into or exchangeable for our common stock, our preferred stock or other securities (including securities of a third party). We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock, our preferred stock or other securities (including securities of a third party) that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indentures will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate. If the debt securities are convertible into or exchangeable for our other securities or securities of other entities, the person with whom we consolidate or merge or to whom we sell all of our property must make provisions for the conversion of the debt securities into securities that the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Events of Default under the Indenture

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indentures with respect to any series of debt securities that we may issue:

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We will describe in each applicable prospectus supplement any additional events of default relating to the relevant series of debt securities.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default arises due to the occurrence of certain specified bankruptcy, insolvency or reorganization events, the unpaid principal, premium, if any, and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity or security satisfactory to it against any loss, liability or expense. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

The indentures provide that if an event of default has occurred and is continuing, the trustee will be required in the exercise of its powers to use the degree of care that a prudent person would use in the conduct of its own affairs. The trustee, however, may refuse to follow any direction that conflicts with law or the indenture, or that the trustee determines is unduly prejudicial to the rights of any other holder of the relevant series of debt securities, or that would involve the trustee in personal liability. Prior to taking any action under the indentures, the trustee will be entitled to indemnification against all costs, expenses and liabilities that would be incurred by taking or not taking such action.

A holder of the debt securities of any series will have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies only if:

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities, or other defaults that may be specified in the applicable prospectus supplement.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indentures.

The indentures provide that if a default occurs and is continuing and is actually known to a responsible officer of the trustee, the trustee must mail to each holder notice of the default within the earlier of 90 days after it occurs and 30 days after it is known by a responsible officer of the trustee or written notice of it is received by the trustee, unless such default has been cured or waived. Except in the case of a default in the payment of principal or premium of, or interest on, any debt security or certain other defaults specified in an indenture, the trustee shall be protected in withholding such notice if and so long as the Board of Directors, the executive committee or a trust

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committee of directors, or responsible officers of the trustee, in good faith determine that withholding notice is in the best interests of holders of the relevant series of debt securities.

Modification of Indenture; Waiver

Subject to the terms of the indenture for any series of debt securities that we may issue, we and the trustee may change an indenture without the consent of any holders with respect to the following specific matters:

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, subject to the terms of the indenture for any series of debt securities that we may issue or otherwise provided in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may only make the following changes with the consent of each holder of any outstanding debt securities affected:

Discharge

Each indenture provides that, subject to the terms of the indenture and any limitation otherwise provided in the prospectus supplement applicable to a particular series of debt securities, we may elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, and any premium and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on

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behalf of, The Depository Trust Company or another depositary named by us and identified in a prospectus supplement with respect to that series. See 'Legal Ownership of Securities' below for a further description of the terms relating to any book-entry securities.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will make no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture and is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur. However, upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest payment.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Ranking Debt Securities

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The subordinated debt securities will be unsecured and will be subordinate and junior in priority of payment to certain other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of subordinated debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

The senior debt securities will be unsecured and will rank equally in right of payment to all our other senior unsecured debt. The senior indenture does not limit the amount of senior debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements and free writing prospectuses, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series. Warrants may be offered independently or together with common stock, preferred stock or debt securities offered by any prospectus supplement, and may be attached to or separate from those securities. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants that we may offer in more detail in the applicable prospectus supplement and any applicable free writing prospectus. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.

We will issue the warrants under a warrant agreement that we will enter into with a warrant agent to be selected by us. The warrant agent will act solely as an agent of ours in connection with the warrants and will not act as an agent for the holders or beneficial owners of the warrants. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from a current report on Form 8-K that we file with the SEC, the form of warrant agreement, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering before the issuance of the related series of warrants. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to a particular series of warrants. We urge you to read the applicable prospectus supplement and any applicable free writing prospectus related to the particular series of warrants that we sell under this prospectus, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants.

General

We will describe in the applicable prospectus supplement the terms relating to a series of warrants, including:

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

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Exercise of Warrants

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Enforceability of Rights by Holders of Warrants

Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

DESCRIPTION OF UNITS

The following description, together with the additional information we may include in any applicable prospectus supplements and free writing prospectuses, summarizes the material terms and provisions of the units that we may offer under this prospectus.

While the terms we have summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. The terms of any units offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.

We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from a current report on Form 8-K that we file with the SEC, the form of unit agreement that describes the terms of the series of units we are offering, and any supplemental agreements, before the issuance of the related series of units. The following summaries of material terms and provisions of the units are subject to, and qualified in their entirety by reference to, all the provisions of the unit agreement and any supplemental agreements applicable to a particular series of units. We urge you to read the applicable prospectus supplements related to the particular series of units that we sell under this prospectus, as well as the complete unit agreement and any supplemental agreements that contain the terms of the units.

General

We may issue units comprised of one or more debt securities, shares of common stock, shares of preferred stock and warrants in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

We will describe in the applicable prospectus supplement the terms of the series of units, including:

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The provisions described in this section, as well as those described under 'Description of Capital Stock,' 'Description of Debt Securities' and 'Description of Warrants' will apply to each unit and to any common stock, preferred stock, debt security or warrant included in each unit, respectively.

Issuance in Series

We may issue units in such amounts and in numerous distinct series as we determine.

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Enforceability of Rights by Holders of Units

Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

We, the unit agents and any of their agents may treat the registered holder of any unit certificate as an absolute owner of the units evidenced by that certificate for any purpose and as the person entitled to exercise the rights attaching to the units so requested, despite any notice to the contrary. See 'Legal Ownership of Securities.'

LEGAL OWNERSHIP OF SECURITIES

We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee or depositary or warrant agent maintain for this purpose as the 'holders' of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as 'indirect holders' of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary's book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Global securities will be registered in the name of the depositary or its participants. Consequently, for global securities, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a global security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary's book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.

Street Name Holders

We may terminate a global security or issue securities that are not issued in global form. In these cases, investors may choose to hold their securities in their own names or in 'street name.' Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any such trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not legal holders, of those securities.

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Legal Holders

Our obligations, as well as the obligations of any applicable trustee or third party employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with its participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of an indenture, or for other purposes. In such an event, we would seek approval only from the legal holders, and not the indirect holders, of the securities. Whether and how the legal holders contact the indirect holders is up to the legal holders.

Special Considerations for Indirect Holders

If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

Global Securities

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we issue to, deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, The Depository Trust Company, New York, New York, known as DTC, will be the depositary for all securities issued in book-entry form.

A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under '- Special Situations When A Global Security Will Be Terminated.' As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and legal holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a legal holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued as a global security, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

Special Considerations For Global Securities

As an indirect holder, an investor's rights relating to a global security will be governed by the account rules of the investor's financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only as global securities, an investor should be aware of the following:

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Special Situations When A Global Security Will Be Terminated

In a few special situations described below, a global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own names, so that they will be direct holders. We have described the rights of holders and street name investors above.

A global security will terminate when the following special situations occur:

The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and neither we, nor any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

PLAN OF DISTRIBUTION

We may sell the securities being offered hereby in one or more of the following ways from time to time:

As set forth in more detail below, the securities may be distributed from time to time in one or more transactions:

We will set forth in a prospectus supplement the terms of that particular offering of securities, including:

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Only underwriters named in the prospectus supplement are underwriters of the securities offered by the prospectus supplement.

If underwriters are used in an offering, we will execute an underwriting agreement with such underwriters and will specify the name of each underwriter and the terms of the transaction (including any underwriting discounts and other terms constituting compensation of the underwriters and any dealers) in a prospectus supplement. The securities may be offered to the public either through underwriting syndicates represented by managing underwriters or directly by one or more investment banking firms or others, as designated. If an underwriting syndicate is used, the managing underwriter(s) will be specified on the cover of the prospectus supplement. If underwriters are used in the sale, the offered securities will be acquired by the underwriters for their own accounts and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Any public offering price and any discounts or concessions allowed or re-allowed or paid to dealers may be changed from time to time. Unless otherwise set forth in the prospectus supplement, the obligations of the underwriters to purchase the offered securities will be subject to conditions precedent and the underwriters will be obligated to purchase all of the offered securities if any are purchased.

We may grant to the underwriters options to purchase additional securities to cover over-allotments, if any, at the public offering price, with additional underwriting commissions or discounts, as may be set forth in a related prospectus supplement. The terms of any over-allotment option will be set forth in the prospectus supplement for those securities.

If we use a dealer in the sale of the securities being offered pursuant to this prospectus or any prospectus supplement, we will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. The names of the dealers and the terms of the transaction will be specified in a prospectus supplement.

We may sell the securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, any agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

In connection with the sale of the securities, underwriters, dealers or agents may receive compensation from us or from purchasers of the common stock for whom they act as agents in the form of discounts, concessions or commissions. Underwriters may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or commissions from the purchasers for whom they may act as agents. Underwriters, dealers and agents that participate in the distribution of the securities, and any institutional investors or others that purchase common stock directly and then resell the securities, may be deemed to be underwriters, and any discounts or commissions received by them from us and any profit on the resale of the common stock by them may be deemed to be underwriting discounts and commissions under the Securities Act.

We may provide agents and underwriters with indemnification against particular civil liabilities, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to such liabilities. Agents and underwriters may engage in transactions with, or perform services for, us in the ordinary course of business.

In addition, we may enter into derivative transactions with third parties (including the writing of options), or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with such a transaction, the third parties may, pursuant to this prospectus and the applicable prospectus supplement, sell securities covered by this prospectus and the applicable prospectus supplement. If so, the third party may use securities borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and the applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and the applicable prospectus supplement. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement or in a post-effective amendment.

To facilitate an offering of a series of securities, persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the market price of the securities. This may include over-allotments or short sales of the securities, which involves

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the sale by persons participating in the offering of more securities than have been sold to them by us. In those circumstances, such persons would cover such over-allotments or short positions by purchasing in the open market or by exercising the over-allotment option granted to those persons. In addition, those persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to underwriters or dealers participating in any such offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. Such transactions, if commenced, may be discontinued at any time. We make no representation or prediction as to the direction or magnitude of any effect that the transactions described above, if implemented, may have on the price of our securities.

Unless otherwise specified in the applicable prospectus supplement, each class or series of securities will be a new issue with no established trading market, other than our common stock, which is listed on the NASDAQ Capital Market. We may elect to list any other class or series of securities on any exchange or market, but we are not obligated to do so. It is possible that one or more underwriters may make a market in a class or series of securities, but the underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot give any assurance as to the liquidity of the trading market for any of the securities.

In order to comply with the securities laws of some states, if applicable, the securities offered pursuant to this prospectus will be sold in those states only through registered or licensed brokers or dealers. In addition, in some states securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and complied with.

Any underwriter may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Overallotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of these activities at any time.

Any underwriters who are qualified market makers on the NASDAQ Capital Market may engage in passive market making transactions in the securities on the NASDAQ Capital Market in accordance with Rule 103 of Regulation M, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security. If all independent bids are lowered below the passive market maker's bid, however, the passive market maker's bid must then be lowered when certain purchase limits are exceeded.

LEGAL MATTERS

The validity of the issuance of the securities offered hereby will be passed upon for us by Sheppard Mullin Richter & Hampton LLP, New York, New York. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

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EXPERTS

The consolidated financial statements as of June 30, 2020 and 2019 and for the years then ended incorporated by reference in this prospectus have been so incorporated in reliance on the report of Armanino LLP, an independent registered public accounting firm, incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus constitutes a part of a registration statement on Form S-3 filed under the Securities Act. As permitted by the SEC's rules, this prospectus and any prospectus supplement, which form a part of the registration statement, do not contain all the information that is included in the registration statement. You will find additional information about us in the registration statement. Any statements made in this prospectus or any prospectus supplement concerning legal documents are not necessarily complete and you should read the documents that are filed as exhibits to the registration statement or otherwise filed with the SEC for a more complete understanding of the document or matter.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read, without charge, and copy the documents we file at the SEC's public reference rooms in Washington, D.C. at 100 F Street, NE, Room 1580, Washington, DC 20549, or in New York, New York and Chicago, Illinois. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. Our SEC filings are also available to the public at no cost from the SEC's website at http://www.sec.gov. In addition, we make available on or through our Internet site copies of these reports as soon as reasonably practicable after we electronically file or furnish them to the SEC. Our Internet site can be found at www.astrotechcorp.com.

INCORPORATION OF DOCUMENTS BY REFERENCE

We have filed a registration statement on Form S-3 with the Securities and Exchange Commission under the Securities Act. This prospectus is part of the registration statement but the registration statement includes and incorporates by reference additional information and exhibits. The Securities and Exchange Commission permits us to 'incorporate by reference' the information contained in documents we file with the Securities and Exchange Commission, which means that we can disclose important information to you by referring you to those documents rather than by including them in this prospectus. Information that is incorporated by reference is considered to be part of this prospectus and you should read it with the same care that you read this prospectus. Information that we file later with the Securities and Exchange Commission will automatically update and supersede the information that is either contained, or incorporated by reference, in this prospectus, and will be considered to be a part of this prospectus from the date those documents are filed. We have filed with the Securities and Exchange Commission, and incorporate by reference in this prospectus:

We also incorporate by reference all additional documents that we file with the Securities and Exchange Commission under the terms of Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act that are made after the date of the initial registration statement but prior to effectiveness of the registration statement and after the date of this prospectus but prior to the termination of the offering of the securities covered by this prospectus. We are not, however, incorporating, in each case, any documents or information that we are deemed to furnish and not file in accordance with Securities and Exchange Commission rules.

You may request, and we will provide you with, a copy of these filings, at no cost, by calling us at (512) 485-9530 or by writing to us at the following address:

Astrotech Corporation

2028 E. Ben White Blvd., Suite 240-9530

Austin, Texas 78741

Attn: Eric Stober, Chief Financial Officer

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Shares of Common Stock

PROSPECTUS SUPPLEMENT

H.C. Wainwright & Co.

, 2021

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