MESA LABORATORIES INC /CO/ - Capital/Financing Update 2019

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As filed with the Securities and Exchange Commission on August 6, 2019.

Registration No. 333-

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

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FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

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MESA LABORATORIES, INC. (Exact name of Registrant as specified in its charter)

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Colorado (State or other jurisdiction of incorporation or organization) 84-0872291 (I.R.S. Employer Identification Number)

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12100 West Sixth Avenue Lakewood, Colorado 80228 303-987-8000 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

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Gary Owens Chief Executive Officer Mesa Laboratories, Inc. 12100 6th Ave. Lakewood, CO 80228 303-987-8000 (Name, address, including zip code, and telephone number, including area code, of agent for service)

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With copies to:

Elizabeth K. Vonne John Elofson Davis Graham & Stubbs LLP 1550 17 th Street, Suite 500 Denver, CO 80202

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Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: ý

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ý

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Securities Exchange Act, as amended or the Exchange Act. (Check one):

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Large accelerated filer o Accelerated filer ý Non-accelerated filer o Smaller reporting company o Emerging growth company o

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act. o

CALCULATION OF REGISTRATION FEE

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Title of Each Class of Securities To Be Registered(1)	Amount to be Registered(1)	Proposed Maximum Offering Price Per Unit(1)	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee
Debt Securities(2)	(3)	(3)	(3)	(3)
Common Stock, no par value	(3)	(3)	(3)	(3)
Preferred Stock, no par value	(3)	(3)	(3)	(3)
Depositary Shares(4)	(3)	(3)	(3)	(3)
Warrants	(3)	(3)	(3)	(3)
Purchase Contracts	(3)	(3)	(3)	(3)
Units(5)	(3)	(3)	(3)	(3)

end of user-specified TAGGED TABLE (1) Securities registered by this registration statement may be sold separately, together or as units with other securities registered hereunder. This registration statement registers an indeterminate aggregate amount or number, as the case may be, of shares of common stock or preferred stock, or of debt securities, depositary shares, warrants, purchase contracts and units of the registrant as may from time to time be issued at currently indeterminable prices and as may be issuable upon conversion, redemption, repurchase, exchange or exercise of any securities registered hereunder, including under any applicable anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable on exercise, conversion or exchange of other securities. (2) The debt securities may be senior, senior subordinated or subordinated and may be secured or unsecured. After the date the debt securities are issued, direct and indirect domestic or foreign subsidiaries of the registrant may become guarantors of some or all of the debt securities registered hereunder. (3) Omitted pursuant to General Instruction II.E. of Form S-3. In accordance with Rules 456(b) and 457(r) under the Securities Act, the registrant is deferring payment of all of the registration fee. (4) Each depositary share will be issued under a deposit agreement, will represent an interest in a fractional share or multiple shares of preferred stock and will be evidenced by a depositary receipt. (5) Each unit will be issued under a unit agreement or indenture and will represent an interest in a combination of any two or more of the securities being registered by this registration statement or debt obligations of third parties, including U.S. Treasury securities.

BLANK LINE TO FORCE PARA

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MESA LABORATORIES, INC.

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Debt Securities

Common Stock

Preferred Stock

Depositary Shares

Warrants

Purchase Contracts

Units

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By this prospectus, we may offer and sell from time to time, in amounts, on terms and at prices that will be determined at the time of offering in one or more offerings, debt securities, common stock, preferred stock, depositary shares, warrants, purchase contracts, units or any combination thereof as described in this prospectus. The warrants may be convertible into or exercisable or exchangeable for common stock or preferred stock, the preferred stock may be convertible into or exchangeable for common stock and the debt securities may be convertible into or exchangeable for common stock or preferred stock. You should carefully read this prospectus, any prospectus supplement and any related free writing prospectus, as well as any documents incorporated in any of the foregoing by reference, before you invest in our securities. This prospectus may not be used to sell our securities unless accompanied by a prospectus supplement. The prospectus supplement or any related free writing prospectus may also add to, update, supplement or clarify information contained in this prospectus.

Our common stock is traded on the Nasdaq Global Select Market under the symbol "MLAB."

We may offer and sell our securities to or through one or more agents, underwriters, dealers or other third parties or directly to one or more purchasers on a continuous or delayed basis. If agents, underwriters or dealers are used to sell our securities, we will name them and describe their compensation in a prospectus supplement. The price to the public of our securities and the net proceeds we expect to receive from the sale of such securities will also be set forth in a prospectus supplement.

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INVESTING IN OUR SECURITIES INVOLVES A HIGH DEGREE OF RISK. YOU SHOULD CAREFULLY REVIEW THE RISKS AND UNCERTAINTIES REFERENCED UNDER THE HEADING "RISK FACTORS" ON PAGE 3 OF THIS PROSPECTUS AS WELL AS THOSE CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT AND ANY RELATED FREE WRITING PROSPECTUS, AND IN THE OTHER DOCUMENTS THAT ARE INCORPORATED BY REFERENCE INTO THIS PROSPECTUS OR THE APPLICABLE 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 is truthful or complete. Any representation to the contrary is a criminal offense.

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BLANK LINE TO FORCE PARA

The date of this prospectus is August 6, 2019.

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ABOUT THIS PROSPECTUS	1
WHERE YOU CAN FIND ADDITIONAL INFORMATION	2
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE	2
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	3
RISK FACTORS	3
ABOUT THE COMPANY	4
DESCRIPTION OF CAPITAL STOCK	4
DESCRIPTION OF DEBT SECURITIES	6
DESCRIPTION OF DEPOSITARY SHARES	14
DESCRIPTION OF WARRANTS	14
DESCRIPTION OF PURCHASE CONTRACTS	15
DESCRIPTION OF UNITS	16
USE OF PROCEEDS	16
PLAN OF DISTRIBUTION	16
LEGAL MATTERS	20
EXPERTS	20

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ABOUT THIS PROSPECTUS

This prospectus is part of an automatic shelf registration statement that we filed with the Securities and Exchange Commission, or the SEC, as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act. Under this shelf registration, we may offer shares of our common stock and preferred stock, debt securities, depositary shares, warrants to purchase common stock or preferred stock, purchase contracts, units, or any combination thereof, from time to time in one or more offerings. This prospectus only provides you with a general description of the securities we may offer. Each time we offer our securities under this prospectus, we will provide a prospectus supplement that will contain more specific information about the specific terms of the 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. This prospectus may not be used to sell our securities unless accompanied by a prospectus supplement. Each such 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 incorporated by reference into this prospectus. We urge you to carefully read this prospectus, any applicable prospectus supplement and any related free writing prospectus, together with the information incorporated herein by reference as described under the headings "Where You Can Find Additional Information" and "Incorporation of Certain Information by Reference" before you invest in our securities.

We have not authorized anyone to provide you with information in addition to or different from that contained or incorporated by reference into this prospectus, any applicable prospectus supplement and any related free writing prospectus. We take no responsibility for, and can provide no assurances as to the reliability of, any information not contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus that we may authorize to be provided to you. This prospectus 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 in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate only as of the date on the front of the document and that any information 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, any applicable 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 contains summaries of certain provisions contained in some of the documents described herein, 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 herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the heading "Where You Can Find Additional Information."

Unless otherwise mentioned or unless the context requires otherwise, throughout this prospectus, any applicable prospectus supplement and any related free writing prospectus, the words "Mesa," "we," "us," "our," the "company" or similar references refer to Mesa Laboratories, Inc. and its subsidiaries; and the term "securities" refers collectively to our common stock, preferred stock, debt securities, depositary shares, warrants to purchase common stock or preferred stock, purchase contracts, units, or any combination of the foregoing securities.

This prospectus and the information incorporated herein by reference contain references to trademarks, service marks and trade names owned by us or other companies. Solely for convenience, trademarks, service marks and trade names referred to in this prospectus and the information incorporated herein, including logos, artwork, and other visual displays, may appear without the ® or symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensor to these

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trademarks, service marks and trade names. We do not intend our use or display of other companies' trade names, service marks or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies. All trademarks, service marks and trade names included or incorporated by reference into this prospectus, any applicable prospectus supplement or any related free writing prospectus are the property of their respective owners.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus is part of a registration statement that we have filed with the SEC. Certain information in the registration statement has been omitted from this prospectus in accordance with the rules of the SEC. We are subject to the information requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and, in accordance therewith, file annual, quarterly and special reports, proxy statements and other information with the SEC. These documents may be accessed through the SEC's Electronic Data Gathering, Analysis and Retrieval system, or EDGAR, via electronic means, including the SEC's home page on the Internet ( www.sec.gov ) or on our website at www.mesalabs.com/investor-relations . The information contained in, or that can be accessed through, our website is not part of this prospectus.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. The information incorporated by reference is an important part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file after the date hereof with the SEC will automatically update and supersede the information in this prospectus. We are incorporating by reference the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any future report or document that is not deemed filed under such provisions, after the date of this prospectus and prior to the termination of this offering:

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or phone number:

Mesa Laboratories, Inc. 12100 West Sixth Avenue Lakewood, CO 80228 Attention: Investor Relations 303-987-8000

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You may also access these documents, free of charge on the SEC's website at www.sec.gov or on our website at www.mesalabs.com/investor-relations . The information contained in, or that can be accessed through, our website is not part of this prospectus.

This prospectus is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as "may," "will," "could," "should," "expects," "intends," "plans," "anticipates," "believes," "estimates," "predicts," "projects," "potential," "continue," and similar expressions, or the negative of these terms, or similar expressions. Accordingly, these statements involve estimates, assumptions and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this report, and in particular those factors referenced in the section "Risk Factors."

This prospectus contains forward- looking statements that are based on our management's belief and assumptions and on information currently available to our management. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements include, but are not limited to, statements about: the acceptance by the market of our products, the implementation of our business model, strategic plans for our business, including potential divestitures of divisions (and the timing of such divestitures) and acquisitions of businesses or new products, products and technology, the scope of protection we are able to establish and maintain for intellectual property rights covering our products and technology, estimates of our expenses, future revenues and capital requirements, our ability to maintain and establish key customer relationships, and our financial performance, developments relating to our competitors and our industry. Given these uncertainties, you should not place undue reliance on these forward-looking statements. You should read this prospectus, any supplements to this prospectus and the documents that we incorporate by reference in this prospectus with the understanding that our actual future results may be materially different from what we expect. Except as required by law, we do not undertake any obligation to update or revise any forward-looking statements contained in this prospectus or any supplement to this prospectus, whether as a result of new information, future events or otherwise.

RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully consider the risks described in the documents incorporated by reference in this prospectus and any prospectus supplement, as well as other information we include or incorporate by reference into this prospectus and any applicable prospectus supplement, before making an investment decision. Our business, financial condition or results of operations could be materially adversely affected by the materialization of any of these risks. The trading price of our securities could decline due to the materialization of any of these risks, and you may lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking

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statements as a result of certain factors, including the risks described in the documents incorporated herein by reference, including (i) our most recent annual report on Form 10-K which is on file with the SEC and is incorporated herein by reference and (ii) other documents we file with the SEC that are deemed incorporated by reference into this prospectus.

ABOUT THE COMPANY

Mesa Laboratories, Inc. designs, manufactures, and markets quality control products and services, many of which are required by regulatory requirements. Our philosophy is to manufacture products of exceptional quality and provide a high level of ongoing service for those products. Our revenues come from product sales, which include hardware and software, and consumables; as well as services, which include installation, discrete maintenance services, and ongoing maintenance contracts. Our strategic goals are to continue to grow revenues and profits through three key strategies(1) improving our commercial channels, (2) introducing new products to the market, and (3) seeking out companies or product lines to acquire.

We were incorporated in Colorado in 1982. Our principal executive offices and corporate headquarters are located at 12100 West Sixth Ave., Lakewood, Colorado 80228, and our telephone number is 303-987-8000. Our website is www.mesalabs.com. The information contained in or connected to our website is not incorporated by reference into this prospectus and should not be considered a part hereof.

DESCRIPTION OF CAPITAL STOCK

In the discussion that follows, we have summarized selected provisions of our Articles of Incorporation and our Bylaws, relating to our capital stock. You should read our Articles of Incorporation and our Bylaws for more details regarding the provisions we describe below and for other provisions that may be important to you. We have filed copies of those documents with the SEC, and they are incorporated by reference as exhibits to the registration statement. Please read "Where You Can Find More Information."

Our authorized capital stock consists of 25,000,000 shares of common stock, no par value, and 1,000,000 shares of preferred stock, no par value. The following is a summary of the material provisions of the common stock and the preferred stock contained in our Articles of Incorporation and Bylaws.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Common Stock

As of August 5, 2019, there were 3,923,982 shares of common stock issued and outstanding.

The holders of our common stock are entitled to one vote per share on all matters to be voted upon by the stockholders. The holders of common stock are entitled to receive ratably dividends, if any, as may be declared from time to time by the board of directors out of funds legally available for that purpose. In the event of our liquidation, dissolution or winding up, the holders of common stock are entitled to share ratably in all assets remaining after payment of liabilities. The common stock has no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to the common stock. Issued shares of common stock for which appropriate consideration have been received are non-assessable and shareholders are not liable for the debts or other obligations of the company.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Preferred Stock

As of August 5, 2019, there were no shares of preferred stock issued and outstanding.

Our Articles of Incorporation authorize our board of directors, subject to any limitations prescribed by law, without further stockholder approval, to establish and to issue from time to time one

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or more classes or series of preferred stock, no par value per share, covering up to an aggregate of 1,000,000 shares of preferred stock. Each class or series of preferred stock will cover the number of shares and will have the powers, preferences, rights, qualifications, limitations and restrictions determined by the board of directors.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Certain Provisions of Our Articles of Incorporation and Bylaws and Colorado Law

Certain provisions of our Articles of Incorporation and our Bylaws could make our acquisition by a third party, a change in our incumbent directors, or a similar change of control more difficult. These provisions, which are summarized below, may discourage certain types of takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors. These provisions of our Articles of Incorporation and Bylaws may also be significant because they define certain of the aspects of our corporate governance.

Election of Directors. Our Bylaws provide that the board of directors may increase the size of our board and designate the directors to fill the vacancies.

No Cumulative Voting. Our Articles of Incorporation provide that no shareholder is permitted to cumulate its votes in the election of directors.

Advance Notice Bylaws. Our Bylaws require a shareholder seeking to nominate a candidate for election as director or to propose other business at a meeting of shareholders to provide us notice of the proposed candidate or business within a specified period in advance of the meeting.

Exclusive Forum. Our Bylaws provide that unless the Company consents in writing to the selection of an alternative forum, the sole and exclusive forum for any of the following shall be a state court within the State of Colorado, or, if no state court located within the State of Colorado has jurisdiction, the federal district court for the District of Colorado: (i) any claim that is based upon a violation of a duty under the laws of Colorado by a current or former director, officer, or shareholder in such capacity, (ii) any derivative action or proceeding brought on behalf of the Company, (iii) any action asserting a claim arising pursuant to any provision of the Colorado Business Corporation Act, the Articles of Incorporation or the Bylaws, (iv) any action asserting a claim governed by the internal affairs doctrine that is not included in (i) through (iii).

Limitations on Liability. Our Articles of Incorporation provide that no person who is or was a director will be personally liable to us or to our shareholders for monetary damages for breach of fiduciary duty as a director, so long as such director acted in good faith, subject to certain exceptions under the Colorado Business Corporation Act.

We have also obtained policies of directors' and officers' liability insurance. These policies insure our directors and officers against the cost of defense, settlement or payment of a judgment under certain circumstances. The existence of such limitation on liability, indemnification and insurance may impede a change of control of us to the extent that a hostile acquirer seeks to litigate its contest for control with our directors and officers.

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The transfer agent for our common stock is Computershare Trust Company, N.A. Its address is 8742 Lucent Blvd., Suite 225, Highlands Ranch, Colorado 80129 and its telephone number is (303) 262-0600.

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Our common stock is quoted on the Nasdaq Global Select Market, or Nasdaq under the trading symbol "MLAB."

DESCRIPTION OF DEBT SECURITIES

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The debt securities that we may offer by this prospectus consist of notes, debentures, or other evidences of our indebtedness, which we refer to collectively as "debt securities." This prospectus describes certain general terms and provisions of the debt securities. When we offer to sell a particular series of debt securities, we will describe the specific terms for the debt securities in a supplement to this prospectus. The prospectus supplement will also indicate whether the general terms and provisions described in this prospectus apply to a particular series of debt securities. The debt securities will be issued under an indenture between us and a trustee named in the prospectus supplement. We have summarized select portions of the form of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement, and you should read the indenture for provisions that may be important to you.

In this description, the words "Mesa," "we," "us," and "our" refer only to Mesa Laboratories, Inc., and not to any of our subsidiaries or affiliates. Additional or different provisions that are applicable to a particular series of debt securities will, if material, be described in a prospectus supplement relating to the offering of debt securities of that series. These provisions may include, among other things and to the extent applicable, the following:

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We may issue debt securities at a discount from their stated principal amount. Federal income tax considerations and other special considerations applicable to any debt security issued with original issue discount (an "original issue discount security") may be described in an applicable prospectus supplement.

If the purchase price of any series of the debt securities is payable in a foreign currency or currency unit or if the principal of or any premium or interest on any series of the debt securities is payable in a foreign currency or currency unit, the restrictions, elections, general tax considerations, specific terms, and other information with respect to the debt securities and the applicable foreign currency or currency unit will be set forth in an applicable prospectus supplement.

Unless otherwise indicated in an applicable prospectus supplement:

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Global Securities

The debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary or its nominee identified in an applicable prospectus supplement. Unless and until it is exchanged in whole or in part for debt securities in registered form, a global security may not be registered for transfer or exchange except:

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The specific terms of the depositary arrangement with respect to any debt securities to be represented by a global security will be described in an applicable prospectus supplement. We expect that the following provisions will apply to depositary arrangements.

Unless otherwise specified in an applicable prospectus supplement, any global security that represents debt securities will be registered in the name of the depositary or its nominee. Upon the deposit of a global security with or on behalf of the depositary for the global security, the depositary will credit, on its book-entry registration and transfer system, the respective principal amounts of the debt securities represented by the global security to the accounts of institutions that are participants in such system. The accounts to be credited will be designated by the underwriters or agents of the debt securities or by us, if the debt securities are offered and sold directly by us.

Ownership of beneficial interests in debt securities represented by a global security will be limited to participants in the book-entry registration and transfer system of the applicable depositary or persons that may hold interests through those participants. Ownership of those beneficial interests by participants will be shown on, and the transfer of ownership will be effected only through, records maintained by the depositary or its nominee for such global security. Ownership of such beneficial interests by persons that hold through such participants will be shown on, and the transfer of such ownership will be effected only through, records maintained by the participants. The laws of some jurisdictions require that specified purchasers of securities take physical delivery of their securities in definitive form. These laws may impair your ability to transfer beneficial interests in a global security.

So long as the depositary for a global security, or its nominee, is the registered owner of the global security, the depositary or the nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by the global security for all purposes under the applicable indenture. Unless otherwise specified in an applicable prospectus supplement, owners of beneficial interests in the global security will not be entitled to have any of the debt securities represented by the global security registered in their names, will not receive or be entitled to receive physical delivery of any such debt securities in certificated form, and will not be considered the owners or holders of the debt securities for any purpose under the applicable indenture. Accordingly, each person owning a beneficial interest in debt securities represented by a global security must rely on the procedures of the applicable depositary and, if the person is not a participant in the book-entry registration and transfer system of the applicable depositary, on the procedures of the participant through which the person owns its interest, to exercise any rights of an owner or holder of debt securities under the applicable indenture.

We understand that, under existing industry practices, if an owner of a beneficial interest in debt securities represented by a global security desires to give any notice or take any action that an owner or holder of debt securities is entitled to give or take under the applicable indenture:

Principal of and any premium and interest on debt securities represented by a global security will be payable in the manner described in an applicable prospectus supplement. Payment of principal of, and any premium or interest on, debt securities represented by a global security will be made to the applicable depositary or its nominee, as the case may be, as the registered owner or the holder of the global security. None of us, the trustee, any paying agent, or the registrar for debt securities represented by a global security will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in those debt securities or for maintaining, supervising, or reviewing any records relating to those beneficial ownership interests.

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COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Certain Covenants

Maintenance of Office or Agency. We will be required to maintain an office or agency in each place of payment for each series of debt securities for notice and demand purposes and for the purposes of presenting or surrendering debt securities for payment, registration of transfer, or exchange.

Paying Agents, Etc. If we act as our own paying agent with respect to any series of debt securities, on or before each due date of the principal of or interest on any of the debt securities of that series, we will be required to segregate and hold in trust for the benefit of the persons entitled to payment a sum sufficient to pay the amount due and to notify the trustee promptly of our action or failure to act. If we have one or more paying agents for any series of debt securities, prior to each due date of the principal of or interest on any debt securities of that series, we will be required to deposit with a paying agent a sum sufficient to pay the amount due and, unless the paying agent is the trustee, to promptly notify the trustee of our action or failure to act. All moneys paid by us to a paying agent for the payment of principal of or interest on any debt securities that remain unclaimed for two years after the principal or interest has become due and payable may be repaid to us, and thereafter the holder of those debt securities may look only to us for payment thereof.

Existence. We will be required to, and will be required to cause our subsidiaries to, preserve and keep in full force and effect our and their existence, charter rights, statutory rights, and franchises, except to the extent that our board of directors determines that the preservation thereof no longer is desirable in the conduct of our business.

Restrictive Covenants. Any restrictive covenants applicable to any series of debt securities will be described in an applicable prospectus supplement.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Events of Default

When we use the term "Event of Default" with respect to debt securities of any series, we generally mean:

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Pursuant to the Trust Indenture Act, the trustee is required, within 90 calendar days after the occurrence of a default in respect of any series of debt securities, to give to the holders of the debt securities of that series notice of all uncured defaults known to it, except that other than in the case of a default of the character contemplated in clause (1) or (2) above, the trustee may withhold notice if and so long as it in good faith determines that the withholding of notice is in the interests of the holders of the debt securities of that series.

If an Event of Default described in clause (6) above occurs, the principal of, premium, if any, and accrued interest on the debt securities of that series will become immediately due and payable without any declaration or other act on the part of the trustee or any holder of the debt securities of that series. If any other Event of Default with respect to debt securities of any series occurs and is continuing, either the trustee or the holders of at least 25% in principal amount of the debt securities of that series may declare the principal amount of all debt securities of that series to be due and payable immediately. However, at any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree based on such acceleration has been obtained, the holders of a majority in principal amount of the debt securities of that series may, under specified circumstances, rescind and annul such acceleration. See "Modification and Waiver" below.

Subject to the duty of the trustee to act with the required standard of care during an Event of Default, the trustee will have no obligation to exercise any of its rights or powers under the applicable indenture at the request or direction of the holders of debt securities, unless holders of debt securities shall have furnished to the trustee reasonable security or indemnity. Subject to the provisions of the applicable indenture, including those requiring security or indemnification of the trustee, the holders of a majority in principal amount of the 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.

No holder of a debt security of any series will have any right to institute any proceeding with respect to the applicable indenture or for any remedy thereunder unless:

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However, the limitations described above do not apply to a suit instituted by a holder of a debt security for enforcement of payment of the principal of and interest on such debt security on or after the applicable due dates for the payment of such principal and interest.

We may be required to furnish to the trustee annually a statement as to our performance of our obligations under the applicable indenture and as to any default in our performance.

Any additional Events of Default with respect to any series of debt securities, and any variations from the foregoing Events of Default applicable to any series of debt securities, will be described in an applicable prospectus supplement.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Modification and Waiver

In general, modifications and amendments of an indenture may be made by us and the trustee with the consent of the holders of not less than a majority in principal amount of the debt securities of each series affected thereby. However, no modification or amendment of an indenture may, without the consent of the holder of each debt security affected thereby:

The holders of at least a majority in principal amount of the debt securities of any series may, on behalf of the holders of all debt securities of that series, waive our compliance with specified covenants of the indenture. The holders of at least a majority in principal amount of the debt securities of any series may, on behalf of the holders of all debt securities of that series, waive any past default under the indenture with respect to that series, except:

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Defeasance

Unless otherwise specified in a prospectus supplement applicable to a particular series of debt securities and except as described below, upon compliance with the applicable requirements described below, we:

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Following any defeasance described in clause (1) or (2) above, we will continue to have specified obligations under the indentures, including obligations to register the transfer or exchange of debt securities of the applicable series; replace destroyed, stolen, lost, or mutilated debt securities of the applicable series; maintain an office or agency in respect of the debt securities of the applicable series; and hold funds for payment to holders of debt securities of the applicable series in trust. In the case of any defeasance described in clause (2) above, any failure by us to comply with our continuing obligations may constitute an Event of Default with respect to the debt securities of the applicable series as described in clause (5) under "Events of Defaults" above.

In order to effect any defeasance described in clause (1) or (2) above, we must irrevocably deposit with the trustee, in trust, money or specified government obligations (or depositary receipts therefor) that through the payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay all of the principal of, premium, if any, and interest on the debt securities of such series on the dates such payments are due in accordance with the terms of such debt securities. In addition:

If we fail to comply with our remaining obligations under an indenture with respect to the debt securities of the applicable series following a defeasance described in clause (2) above and the debt securities of that series are declared due and payable because of the occurrence of any undefeased Event of Default, the amount of money and government obligations on deposit with the trustee may be insufficient to pay amounts due on the debt securities of that series at the time of the acceleration resulting from such Event of Default. However, we will remain liable in respect of such payments.

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COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Satisfaction and Discharge

We, at our option, may satisfy and discharge an indenture (except for specified obligations of us and the trustee, including, among others, the obligations to apply money held in trust) when:

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Limitations on Merger and Other Transactions

Prior to the satisfaction and discharge of an indenture, we may not consolidate with or merge with or into any other person, or transfer all or substantially all of our properties and assets to another person unless:

The continuing, surviving, or successor person will succeed to and be substituted for us with the same effect as if it had been named in the indenture as a party thereto, and thereafter the predecessor person will be relieved of all obligations and covenants under the indenture and the debt securities.

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COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Governing Law

The indenture, and the debt securities issued thereunder will be, governed by, and construed in accordance with, the laws of the State of New York.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Regarding the Trustee

The indenture contains specified limitations on the rights of the trustee, should it become our creditor within three months of, or subsequent to, a default by us to make payment in full of principal of or interest on any series of debt securities issued pursuant to the applicable indenture when and as the same becomes due and payable, to obtain payment of claims, or to realize for its own account on property received in respect of any such claim as security or otherwise, unless and until such default is cured. However, the trustee's rights as our creditor will not be limited if the creditor relationship arises from, among other things:

The indenture does not prohibit the trustee from serving as trustee under any other indenture to which we may be a party from time to time or from engaging in other transactions with us. If the trustee acquires any conflicting interest within the meaning of the Trust Indenture Act of 1939 and there is an Event of Default with respect to any series of debt securities, the trustee must eliminate the conflict or resign.

DESCRIPTION OF DEPOSITARY SHARES

We may offer depositary shares (either separately or together with other securities) representing fractional shares of preferred stock of any series. In connection with the issuance of any depositary shares, we will enter into a deposit agreement with a bank or trust company, as depositary, which will be named in the applicable prospectus supplement. Depositary shares will be evidenced by depositary receipts issued pursuant to the related deposit agreement. Immediately following our issuance of the security related to the depositary shares, we will deposit the shares of preferred stock with the relevant depositary and will cause the depositary to issue, on our behalf, the related depositary receipts. Subject to the terms of the deposit agreement, each owner of a depositary receipt will be entitled, in proportion to the fraction of a share of preferred stock represented by the related depositary share, to all the rights, preferences and privileges of, and will be subject to all of the limitations and restrictions on, the preferred stock represented by the depositary receipt (including, if applicable, dividend, voting, conversion, exchange, redemption, sinking fund, repayment at maturity, subscription and liquidation rights).

DESCRIPTION OF WARRANTS

We may issue warrants for the purchase of debt securities, common stock, preferred stock, depositary shares, or any combination thereof. We may issue warrants independently or together with

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any other securities offered by a prospectus supplement. Warrants may be attached to or separate from such securities. Each series of warrants will be issued under a separate warrant agreement we will enter into with a warrant agent specified in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants of a particular series and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

The applicable prospectus supplement will describe the terms of the warrants in respect of which this prospectus is being delivered, including, to the extent applicable, the following:

DESCRIPTION OF PURCHASE CONTRACTS

We may issue purchase contracts, including contracts obligating holders to purchase from us, and for us to sell to holders, a specific or varying number of debt securities, shares of our common stock or preferred stock, depositary shares, warrants or securities of an entity unaffiliated with us, or any combination of the above, at a future date or dates. Alternatively, the purchase contracts may obligate us to purchase from holders, and obligate holders to sell to us, a specific or varying number or amount of debt securities, shares of our common stock or preferred stock, depositary shares, warrants or other property. The price per share of preferred stock or common stock or price of other securities may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula described in the purchase contracts. We may issue purchase contracts separately or as a part of units each consisting of a purchase contract and debt securities, preferred securities, common securities, warrants or debt obligations of third parties, including U.S. Treasury securities, securing the holder's obligations under the purchase contract. The purchase contracts may require us to make periodic payments to holders, or may require holders to make periodic payments to us, and the payments may be unsecured or pre-funded on some basis. The purchase contracts may require holders to secure the

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holder's obligations in a specified manner that we will describe in the applicable prospectus supplement which we file with the SEC in connection with a public offering relating to the purchase contracts.

The applicable prospectus supplement will describe the terms of any purchase contracts in respect of which this prospectus is being delivered, including, to the extent applicable, the following:

DESCRIPTION OF UNITS

We may issue units comprising one or more securities described in this prospectus in any combination. Units may also include debt obligations of third parties, such as U.S. Treasury securities. Each unit will be issued so that the holder of the unit also is the holder of each security included in the unit. Thus, the holder of each 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.

USE OF PROCEEDS

We intend to use the net proceeds from this offering for general corporate purposes or for other purposes described in a prospectus supplement.

PLAN OF DISTRIBUTION

We may sell the securities offered by this prospectus from time to time in one or more transactions, including without limitation:

Each time we sell securities, we will provide a prospectus supplement that will name any underwriter, dealer or agent involved in the offer and sale of the securities. The prospectus supplement will also set forth the terms of the offering, including the purchase price of the securities and the proceeds to the issuer(s) from the sale of the securities, any underwriting discounts and other items constituting underwriters' compensation and any discounts or concessions allowed or reallowed or paid to dealers and any securities exchanges on which the securities may be listed. Each time we sell securities, we will describe the method of distribution of the securities in the prospectus supplement relating to the transaction.

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In addition, the manner in which we may sell some or all of the securities covered by this prospectus includes, without limitation, through:

We may also enter into hedging transactions. For example, we may:

In addition, we may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with such a transaction, the third parties may sell securities covered by and pursuant to this prospectus and an applicable prospectus supplement or pricing supplement, as the case may be. 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 an 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 or pricing supplement, as the case may be.

A prospectus supplement with respect to each series of securities will state the terms of the offering of the securities, including:

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The offer and sale of the securities described in this prospectus by us, the underwriters or the third parties described above may be effected from time to time in one or more transactions, including privately negotiated transactions, either:

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" General

Any public offering price and any discounts, commissions, concessions or other items constituting compensation allowed or reallowed or paid to underwriters, dealers, agents or remarketing firms may be changed from time to time. Underwriters, dealers, agents and remarketing firms that participate in the distribution of the offered securities may be "underwriters" as defined in the Securities Act. Any discounts or commissions they receive from us and any profits they receive on the resale of the offered securities may be treated as underwriting discounts and commissions under the Securities Act. We will identify any underwriters, agents or dealers and describe their commissions, fees or discounts in the applicable prospectus supplement or pricing supplement, as the case may be.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Underwriters and Agents

If underwriters are used in a sale, they will acquire the offered securities for their own account. The underwriters may resell the offered securities in one or more transactions, including negotiated transactions. These sales may be made at a fixed public offering price or prices, which may be changed, at market prices prevailing at the time of the sale, at prices related to such prevailing market price or at negotiated prices. We may offer the securities to the public through an underwriting syndicate or through a single underwriter. The underwriters in any particular offering will be mentioned in the applicable prospectus supplement or pricing supplement, as the case may be.

Unless otherwise specified in connection with any particular offering of securities, the obligations of the underwriters to purchase the offered securities will be subject to certain conditions contained in an underwriting agreement that we will enter into with the underwriters at the time of the sale to them. The underwriters will be obligated to purchase all of the securities of the series offered if any of the securities are purchased, unless otherwise specified in connection with any particular offering of securities. Any initial public offering price and any discounts or concessions allowed, reallowed or paid to dealers may be changed from time to time.

We may designate agents to sell the offered securities. Unless otherwise specified in connection with any particular offering of securities, the agents will agree to use their best efforts to solicit purchases for the period of their appointment. We may also sell the offered securities to one or more remarketing firms acting as principals for their own accounts or as agents for us. These firms will remarket the offered securities upon purchasing them in accordance with a redemption or repayment pursuant to the terms of the offered securities. A prospectus supplement or pricing supplement, as the case may be, will identify any remarketing firm and will describe the terms of its agreement, if any, with us and its compensation.

In connection with offerings made through underwriters or agents, we may enter into agreements with such underwriters or agents pursuant to which we receive our outstanding securities in consideration for the securities being offered to the public for cash. In connection with these arrangements, the underwriters or agents may also sell securities covered by this prospectus to hedge

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their positions in these outstanding securities, including in short sale transactions. If so, the underwriters or agents may use the securities received from us under these arrangements to close out any related open borrowings of securities.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Dealers

We may sell the offered securities to dealers as principals. We may negotiate and pay dealers' commissions, discounts or concessions for their services. The dealer may then resell such securities to the public either at varying prices to be determined by the dealer or at a fixed offering price agreed to with us at the time of resale. Dealers engaged by us may allow other dealers to participate in resales.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Direct Sales

We may choose to sell the offered securities directly. In this case, no underwriters or agents would be involved.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Institutional Purchasers

We may authorize agents, dealers or underwriters to solicit certain institutional investors to purchase offered securities on a delayed delivery basis pursuant to delayed delivery contracts providing for payment and delivery on a specified future date. The applicable prospectus supplement or pricing supplement, as the case may be, will provide the details of any such arrangement, including the offering price and commissions payable on the solicitations.

We will enter into such delayed contracts only with institutional purchasers that we approve. These institutions may include commercial and savings banks, insurance companies, pension funds, investment companies and educational and charitable institutions.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Indemnification; Other Relationships

We may have agreements with agents, underwriters, dealers and remarketing firms to indemnify them against certain civil liabilities, including liabilities under the Securities Act. Agents, underwriters, dealers and remarketing firms, and their affiliates, may engage in transactions with, or perform services for, us in the ordinary course of business. This includes commercial banking and investment banking transactions.

COMMAND=STYLE_ADDED,"margin-left:10.0pt;text-indent:-10.0pt;" Market Making, Stabilization and Other Transactions

There is currently no market for any of the offered securities other than our common stock, which is listed on Nasdaq. If the offered securities are traded after their initial issuance, they may trade at a discount from their initial offering price, depending upon prevailing interest rates, the market for similar securities and other factors. While it is possible that an underwriter could inform us that it intended to make a market in the offered securities, such underwriter would not be obligated to do so, and any such market making could be discontinued at any time without notice. Therefore, no assurance can be given as to whether an active trading market will develop for the offered securities. We have no current plans for listing of the debt securities, preferred stock or warrants on any securities exchange; any such listing with respect to any particular debt securities, preferred stock or warrants will be described in the applicable prospectus supplement or pricing supplement, as the case may be.

In connection with any offering, the underwriters may purchase and sell shares of common stock in the open market. These transactions may include short sales, syndicate covering transactions and stabilizing transactions. Short sales involve syndicate sales of common stock in excess of the number of shares to be purchased by the underwriters in the offering, which creates a syndicate short position. "Covered" short sales are sales of shares made in an amount up to the number of shares represented

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by the underwriters' over-allotment option. In determining the source of shares to close out the covered syndicate short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the over-allotment option. Transactions to close out the covered syndicate short involve either purchases of the common stock in the open market after the distribution has been completed or the exercise of the over-allotment option. The underwriters may also make "naked" short sales of shares in excess of the over-allotment option. The underwriters must close out any naked short position by purchasing shares of common stock in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering. Stabilizing transactions consist of bids for or purchases of shares in the open market while the offering is in progress for the purpose of pegging, fixing or maintaining the price of the securities.

In connection with any offering, the underwriters may also engage in penalty bids. Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a syndicate covering transaction to cover syndicate short positions. Stabilizing transactions, syndicate covering transactions and penalty bids may cause the price of the securities to be higher than it would be in the absence of the transactions. The underwriters may, if they commence these transactions, discontinue them at any time.

LEGAL MATTERS

The validity of the securities offered by this prospectus and certain other legal matters will be passed upon for us by Davis Graham & Stubbs LLP, Denver, Colorado. If certain legal matters in connection with an offering of the securities made by this prospectus are passed on by counsel for the underwriters of such offering, that counsel will be named in the applicable prospectus supplement related to that offering.

EXPERTS

Plante & Moran, PLLC independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended March 31, 2019 , and the effectiveness of our internal control over financial reporting as of March 31, 2019, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our consolidated financial statements are incorporated by reference in reliance on Plante & Moran, PLLC's reports, given on their authority as experts in accounting and auditing.

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MESA LABORATORIES, INC.

Common Stock

Preferred Stock

Debt Securities

Warrants

Purchase Contracts

Units

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PROSPECTUS

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August 6, 2019

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PART II INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following table sets forth the estimated costs and expenses, other than underwriting discounts and commissions, in connection with the issuance and distribution of the securities registered hereby. The registrant is deferring payment of the registration fee in reliance on Rule 456(b) and Rule 457(r) under the Securities Act. All the amounts shown are estimates.

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SEC registration fee	Amount to be Paid — $	(1)
Nasdaq listing fee		(2)
Accounting fees and expenses		(2)
Legal fees and expenses		(2)
Trustee and Transfer Agent fees and expenses		(2)
Printing fees		(2)
Miscellaneous		(2)

Total	$	(2)

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(1) Omitted because the registration fee is being deferred pursuant to Rule 456(b) and Rule 457(r) under the Securities Act. (2) These fees and expenses depend on the securities offered and the number of issuances, and accordingly cannot be estimated at this time and will be reflected in the applicable prospectus supplement.

Item 15. Indemnification of Directors and Officers.

Article 109 of the Colorado Business Corporation Act ("CBCA") provides broad authority for indemnification of directors and officers. The Articles of Incorporation and Bylaws of Mesa Laboratories, Inc. (the "Registrant") provide for indemnification of its officers and directors to the fullest extent permitted by the CBCA. As permitted by Section 7-108-402 of the CBCA, the Registrant's Articles of Incorporation provide that a director shall not be liable for monetary damages for breach of his fiduciary duty as a director except in certain limited circumstances.

The Company has obtained a directors' and officers' liability insurance policy.

Item 16. Exhibits and Financial Statement Schedules.

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Exhibit No.	Description
*1.1	Form of Underwriting Agreement.
4.1	Form of Indenture.
*4.2	Form of certificate of designations for preferred stock.
*4.3	Form of depositary receipt.
*4.4	Form of depositary agreement.
*4.5	Form of warrant.

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II-1

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Exhibit No.	Description
*4.6	Form of warrant agreement.
*4.7	Form of purchase contract.
*4.8	Form of unit certificate.
*4.9	Form of unit agreement.
5.1	Opinion of Davis Graham & Stubbs LLP.
23.1	Consent of Plante & Moran, PLLC.
23.2	Consent of Davis Graham & Stubbs LLP (included in Exhibit 5.1).
25.1	Form T-1 Statement of Eligibility of Trustee for the Indenture.

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To be filed by an amendment or as an exhibit to a document filed under the Securities Act or the Exchange Act, or otherwise filed, and incorporated by reference herein.

Item 17. Undertakings.

The undersigned registrant hereby undertakes:

II-2

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II-3

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II-4

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THIS IS THE END OF A COMPOSITION COMPONENT

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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Date: August 6, 2019	MESA LABORATORIES, INC. Registrant — By:	/s/ GARY M. OWENS Gary M. Owens Chief Executive Officer

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Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

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Name	Title	Date
/s/ JOHN J. SULLIVAN, PH.D. John J. Sullivan	Chairman of the Board of Directors	August 6, 2019
/s/ GARY M. OWENS Gary M. Owens	Chief Executive Officer, President, and Director	August 6, 2019
/s/ JOHN V. SAKYS John V. Sakys	Chief Financial and Chief Accounting Officer, Secretary and Treasurer	August 6, 2019
/s/ DAVID PEREZ David Perez	Director	August 6, 2019
/s/ JOHN B. SCHMIEDER John B Schmieder	Director	August 6, 2019
/s/ JENNIFER S. ALLTOFT Jennifer S. Alltoft	Director	August 6, 2019
/s/ ROBERT V. DWYER Robert V. Dwyer	Director	August 6, 2019

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II-5

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Name	Title	Date
/s/ EVAN GUILLEMIN Evan Guillemin	Director	August 6, 2019
/s/ DAVID M. KELLY David M. Kelly	Director	August 6, 2019

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II-6

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MESA LABORATORIES INC /CO/ Capital/Financing Update 2019

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MESA LABORATORIES INC /CO/ — Capital/Financing Update 2019

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