(1)	Title of each class of securities to which transaction applies:

(2)	Aggregate number of securities to which transaction applies:

(3)	Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):

(4)	Proposed maximum aggregate value of transaction:

(5)	Total fee paid:

(1)	Amount previously paid:

(2)	Form, Schedule or Registration Statement No.:

(3)	Filing Party:

(4)	Date Filed:

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1.	To elect three Class I directors nominated by the Board of Directors, each to serve for a three-year term, and to elect one Class III director nominated by the Board of Directors, to serve for a two-year term, and in each case until their successors are duly elected and qualified.

4.	To consider and act upon any other business that may properly come before the meeting or any adjournment or postponement of the meeting.

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•	deliver robust organic revenue growth, supplemented by growth from acquisitions;

•	invest in new technologies, in our manufacturing assets and business systems, and in our people;

•	enhance margins and drive working capital efficiencies through manufacturing insourcing and performance improvement;

•	create stronger operating leverage in the business by growing revenue faster than expenses; and

•	fully integrate acquired businesses to generate cost and revenue synergies.

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•	election of three Class I directors nominated by the Board of Directors, each to serve for a three-year term, and the election of one Class III director nominated by the Board of Directors, for a two-year term, and in each case until their successors are duly elected and qualified;

•	an advisory vote on the compensation of our named executive officers (the “say-on-pay” vote); and

•	ratification of the appointment of KPMG LLP as our independent registered public accounting firm for fiscal 2020.

•	Obtaining an Admission Ticket. In order to obtain an admission ticket, please email us at annualmeeting@mrcy.com.

•	Security Measures. Upon entering the meeting facility, you may be required to proceed through a security checkpoint. In addition, cameras, recording equipment, electronic devices, large bags, briefcases, and packages will not be permitted in the annual meeting.

•	Beneficial Shareholders. If you own shares through a broker, bank, or other holder of record (that is, your shares are held in “street name”), you must instruct the holder of record how to vote your shares. In order to provide voting instructions to the holder of record of your shares, please refer to the materials forwarded by your broker, bank, or

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Registered Shareholders. If you own shares that are registered in your name, you may vote by proxy before the annual meeting by internet at www.envisionreports.com/MRCY, by calling 1-800-652-VOTE (8683), or by signing and returning your proxy card. To vote by internet or telephone, you will need your voting control number, which can be found on your proxy card. Proxies submitted by internet or telephone must be received by 11:59 p.m., Eastern Time, on October 22, 2019. If you return a signed proxy card but do not provide voting instructions for some or all of the matters to be voted on, your shares will be voted on all uninstructed matters in accordance with the recommendations of the Board.

•	FOR the election of the nominees for three Class I directors and one Class III director named below under “Proposal 1: Election of Three Class I Directors and One Class III Director;”

•	FOR the approval of, on an advisory basis, the compensation of our named executive officers as disclosed in this proxy statement;

•	FOR the ratification of the appointment of KPMG LLP as our independent registered public accounting firm for fiscal 2020; and

•	in the proxy’s discretion as to any other business which may properly come before the meeting or any adjournment or postponement of the meeting.

•	Beneficial Shareholders. Beneficial shareholders should contact their broker, bank, or other holder of record for instructions on how to revoke their proxies or change their vote.

•

Registered Shareholders. Registered shareholders may revoke their proxies or change their voting instructions at any time before 11:59 p.m., Eastern Time, on October 22, 2019, by submitting a proxy via internet, telephone, or mail that is dated later than the original proxy or by delivering written notice of revocation to our Corporate Secretary. Registered shareholders may also revoke their proxies or change their vote by attending the annual meeting and voting by ballot.

•	Election of directors. A director nominee receiving a majority of the votes properly cast at the meeting for the nominee’s election (meaning he or she receives more votes cast “FOR” than cast “WITHHOLD”) will be elected director. Abstentions and broker non-votes, which are described above, will have no effect on the outcome of voting on these matters.

•	All other proposals. All of the other proposals at the meeting require the favorable vote of a majority of the votes cast on the matter. Abstentions and broker non-votes, which are described above, will have no effect on the outcome of voting on these matters.

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•	the name and address of the shareholder and each of his or her nominees;

•	a description of all arrangements or understandings between the shareholder and each such nominee;

•	such other information as would be required to be included in a proxy statement soliciting proxies for the election of the nominees of such shareholder; and

•	the consent of each nominee to serve as a Director if so elected.

•	the number of all shares of Mercury stock held of record, owned beneficially (directly or indirectly) and represented by proxy by such shareholder as of the date of such notice and as of one year prior to the date of such notice;

•	a description of all arrangements or understandings between such shareholder and each nominee and any other person or persons (naming such person or persons) pursuant to which the nomination or nominations are to be made by such shareholder;

•	a description of any derivative position held or beneficially held (directly or indirectly) by such shareholder with respect to Mercury stock;

•	a description of any proxy, contract, arrangement, understanding, or relationship between such shareholder and any other person or persons (including their names and addresses) in connection with the nomination or nominations to be made by such shareholder or pursuant to which such shareholder has a right to vote any Mercury stock; and

•	a description of any proportionate interest in Mercury stock or derivative positions with respect to Mercury held, directly or indirectly, by a general or limited partnership in which such shareholder is a general partner or, directly or indirectly, beneficially owns an interest in such a general partner.

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•	setting the compensation of our executive officers;

•	reviewing and approving employment agreements, consulting arrangements, severance or retirement arrangements, and change-in-control arrangements or provisions covering any of our current or former executive officers;

•	overseeing the administration of our equity-based and other long-term incentive plans;

•	exercising any fiduciary, administrative, or other function assigned to the committee under any of our health, benefit, or welfare plans, including our 401(k) retirement savings plan;

•	reviewing the compensation and benefits for non-employee directors and making recommendations for any changes to our Board; and

•	overseeing the development and implementation of succession planning for our senior executives.

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•	identifying and evaluating global security, political, budgetary, regulatory and other issues, trends, opportunities, and challenges that could impact our business activities and performance;

•	making recommendations to continue to raise our visibility in the marketplace and awareness of our commercial business model, as well as our products and capabilities; and

•	making recommendations concerning our government relations activities, including our interactions with local, state and federal government on matters of impact to our business with the aim of enhancing our customer base.

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(1)	The Board has determined that each of Messrs. Bass, Nearhos, and O’Brien and Ms. Disbrow qualifies as an “audit committee financial expert” under Securities and Exchange Commission (SEC) rules.

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Our compensation program consists of both fixed and variable components, as well as short and long-term performance measures. The fixed portion (i.e., base salary) provides a steady income to our employees regardless of the performance of our business or stock price. The variable portion (i.e., bonus and equity awards) is based upon our financial performance against short- and long-term objectives and multi-year time-based vesting criteria. This mix of compensation is designed to motivate our employees, including our executive officers, to produce superior short- and long-term corporate performance without taking unnecessary or excessive risks to the detriment of important business metrics.

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For the variable portion of compensation, the executive bonus program is focused on profitability while the executive equity program awards have a mix of time-based and multi-year performance-based vesting. We believe that these programs provide a check on excessive risk taking because to inappropriately benefit one would be a detriment to the other. In addition, we prohibit all our executive officers from short selling Mercury stock or from buying or selling puts, calls, or other derivative securities related to Mercury stock. By prohibiting such hedging transactions our executives cannot insulate themselves from the effects of poor stock performance.

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In order for any employee, including our executive officers, to be eligible for the corporate financial performance element of our bonus program, we must first achieve a certain level of profitability that is established by the Compensation Committee (we refer to this metric as “adjusted EBITDA”). We believe that focusing on profitability rather than other measures encourages a balanced approach to our performance and emphasizes consistent behavior across the organization.

•	Our executive bonus program payout is capped, as are our performance equity awards. We believe this mitigates excessive risk taking by limiting payouts even if we dramatically exceed our financial targets and other performance metrics.

•	Our bonus program has been structured around attaining a certain level of profitability for several years and we have seen no evidence that it encourages unnecessary or excessive risk taking.

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•	the vesting of annual restricted stock awards for non-employee directors would change from 50% vesting on the grant date and 50% vesting on the first anniversary of the grant date to 100% vesting on the first anniversary of the grant date.

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(1)

This column represents the grant date fair value of restricted stock awards for fiscal 2019 in accordance with FASB ASC Topic 718. The grant date fair value of the restricted stock awards granted to non-employee directors in fiscal 2018 has been calculated by multiplying the number of shares granted by the closing price of our common stock as reported on the NASDAQ Global Select Market on the date of grant.

(2)	Mr. Muellner passed away on February 11, 2019 and the amounts above reflect a partial year of cash retainer payments.

(3)	Mr. Nearhos was elected to the Board of Directors on November 26, 2018 and the amounts above reflect a new director restricted stock award and a partial year of cash retainer payments.

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(1)	Does not include outstanding unvested restricted stock awards.

(2)	Consists of our 2018 Stock Incentive Plan, as amended and restated (“2018 Plan”) and our 1997 Employee Stock Purchase Plan, as amended and restated (“ESPP”).

(3)	Does not include purchase rights under the ESPP, as the purchase price and number of shares to be purchased is not determined until the end of the relevant purchase period.

(4)	Includes 118,007 shares available for future issuance under the ESPP and 3,512,088 shares available for future issuance under the 2018 Plan.

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(1)	Based on a Schedule 13G/A filed by Black Rock, Inc. with the SEC on January 29, 2019, reporting beneficial ownership as of December 31, 2018. The reporting entity’s address is 55 East 52nd Street, New York, New York 10022.

(2)	Based on a Schedule 13G/A filed by Vanguard Group, Inc. with the SEC on August 9, 2019, reporting beneficial ownership as of July 31, 2019. The reporting entity’s address is 100 Vanguard Boulevard, Malvern, PA 19355.

(1)	The number and percent of the shares of common stock with respect to each beneficial owner are calculated by assuming that all shares which may be acquired by such person within 60 days of August 19, 2019 are outstanding.

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(2)	Includes (a) 255,120 shares owned by Mr. Aslett individually; and (b) 117,193 restricted shares awarded to Mr. Aslett under our stock-based plans (as to which Mr. Aslett has sole voting power, but which are subject to restrictions on transfer).

(3)	Includes (a) 69,173 shares owned by Mr. Bass individually; and (b) 1,446 restricted shares awarded to Mr. Bass under our stock-based plans (as to which Mr. Bass has sole voting power, but which are subject to restrictions on transfer).

(4)	Includes (a) 73,991 shares owned by Mr. Daniels individually; and (b) 1,446 restricted shares awarded to Mr. Daniels under our stock-based plans (as to which Mr. Daniels has sole voting power, but which are subject to restrictions on transfer).

(5)	Includes (a) 6,509 shares owned by Ms. Disbrow individually; and (b) 1,446 restricted shares awarded to Ms. Disbrow under our stock-based plans (as to which Ms. Disbrow has sole voting power, but which are subject to restrictions on transfer).

(6)	Includes (a) 6,509 shares owned by Ms. Krakauer individually; and (b) 1,446 restricted shares awarded to Ms. Krakauer under our stock-based plans (as to which Ms. Krakauer has sole voting power, but which are subject to restrictions on transfer).

(7)	Includes 4,584 restricted shares awarded to Mr. Nearhos under our stock-based plans (as to which Mr. Nearhos has sole voting power, but which are subject to restrictions on transfer).

(8)	Includes (a) 58,469 shares owned by family trusts controlled by Mr. O’Brien; and (b) 1,446 restricted shares awarded to Mr. O’Brien under our stock-based plans (as to which Mr. O’Brien has sole voting power, but which are subject to restrictions on transfer).

(9)	Includes (a) 80,985 shares owned by Mr. Vitto individually; and (b) 1,446 restricted shares awarded to Mr. Vitto under our stock-based plans (as to which Mr. Vitto has sole voting power, but which are subject to restrictions on transfer).

(10)	Includes (a) 45,005 shares owned by Mr. Cambria individually; and (b) 32,147 restricted shares awarded to Mr. Cambria under our stock-based plans (as to which Mr. Cambria has sole voting power, but which are subject to restrictions on transfer).

(11)	Includes (a) 83,419 shares owned by Mr. Ruppert individually; and (b) 55,333 restricted shares awarded to Mr. Ruppert under our stock-based plans (as to which Mr. Ruppert has sole voting power, but which are subject to restrictions on transfer).

(12)	Includes (a) 244,996 shares owned by Mr. Thibaud individually; and (b) 47,369 restricted shares awarded to Mr. Thibaud under our stock-based plans (as to which Mr. Thibaud has sole voting power, but which are subject to restrictions on transfer).

(13)	Includes (a) 924,176 shares owned by directors and executive officers individually; and (b) 265,302 restricted shares awarded to the directors and executive officers under our stock-based plans (as to which each has sole voting power, but which are subject to restrictions on transfer).

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•	deliver robust organic revenue growth, supplemented by growth from acquisitions;

•	invest in new technologies, in our manufacturing assets and business systems, and in our people;

•	enhance margins and drive working capital efficiencies through manufacturing insourcing and performance improvement;

•	create stronger operating leverage in the business by growing revenue faster than expenses; and

•	fully integrate acquired businesses to generate cost and revenue synergies.

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•	who are engaged, developed, challenged to achieve their full potential;

•	who are aligned to aggressive personal and business objectives; and

•	who are rewarded for their contribution to the achievement of Mercury’s goals, as a leading commercial provider of secure sensor and safety-critical mission processing subsystems.

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•	base salary;

•	target bonus;

•	total target cash compensation (i.e., base salary plus target bonus);

•	target long-term incentive compensation, which consists of equity awards; and

•	target total direct compensation (i.e., target cash plus target long-term incentive compensation).

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•	any award granted to the CEO is subject to ratification by a majority of the independent directors on the Board; and

•	the Compensation Committee may delegate to the CEO the authority to grant awards to other employees (other than our executive officers or other persons deemed to be “covered employees” within the meaning of Section 162(m) of the Code), subject to guidelines that are included in any such delegation.

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(1)

Represents the aggregate grant date fair value for equity awards made to our named executive officers in fiscal years 2017, 2018, and 2019. The amounts reported in this table do not reflect whether the named executive officer has actually realized a financial benefit from the award. Grant date fair value of equity awards is computed in accordance with Accounting Standards Codification Topic 718 (ASC Topic 718). For a discussion of the assumptions and methodologies used to calculate grant date fair value in this proxy statement, please refer to Note B of the financial statements in our annual report on Form 10-K for the fiscal year ended June 30, 2019. For the annual performance-based restricted stock awards, these amounts reflect the grant date fair value of such awards based upon the probable outcome at the time of grant. The maximum potential value of the annual performance-based restricted stock awards (assuming the highest level of performance achievement) that could be earned in the performance period was: Mr. Aslett – $3,795,334; Mr. Cambria – $1,132,194; Mr. Ruppert – $1,248,750; and Mr. Thibaud – $1,665,000.

(2)	The aggregate amounts in this column reflect payments under our executive bonus program. The table below shows the components of our executive bonus program earned for fiscal 2019:

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(a)	The amounts in this column represent our matching contributions allocated to each of the named executive officers who participate in our 401(k) retirement savings plan (subject to IRS limits on contributions to the 401(k) plan). All such matching contributions vest based upon the same vesting schedule used for all other employees.

(b)	The amounts in this column include payments we made to the named executive officers for personal tax and financial planning.

(c)	The amounts in this column represent the reimbursement of relocation costs in connection with Mr. Ruppert's relocation to the Company's headquarters in Andover, MA from the Company's location in Arlington, VA. The amount in this table reflects the reimbursements made in fiscal 2019.

(5)	Mr. Cambria joined the Company in August 2016. His non-equity incentive plan compensation is pro-rated for the portion of fiscal 2017 that he worked for the Company and his equity award reflects a new hire award.

(6)	Mr. Ruppert joined Mercury in 2014 as Senior Vice President of Strategy and Corporate Development and was appointed to the position of Executive Vice President, Chief Financial Officer, and Treasurer in February 2018.

(7)	A portion of Mr. Thibaud’s salary in fiscal years 2017, 2018, and 2019 was paid in Euros. The salary column reflects the conversion of each monthly payment from Euros into U.S. Dollars (USD) based on the average conversion rate between Euros and USD for such month. The amounts in the “Non-Equity Incentive Plan Compensation” column were paid in USD.

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(3)

The amounts shown in these rows reflect the possible cash amounts that could have been earned under the corporate financial performance portion of our executive bonus program for fiscal 2019 upon achievement of the threshold, target, and maximum performance objectives for that program. Payouts for corporate financial performance for fiscal 2019 were subject to the payout formula included in the Compensation Discussion & Analysis. The actual payouts for fiscal 2019 are reflected in the column titled “Non-Equity Incentive Plan Compensation” in the Summary Compensation Table.

(4)	The amounts shown in these rows reflect the maximum cash amounts that could have been earned under the over-achievement portion of our executive bonus program for fiscal 2019. There are no minimum or target payouts under the over-achievement portion of our bonus program, only a cap.

(5)

Mr. Thibaud’s threshold, target, and maximum performance targets under our executive bonus program for fiscal 2019 were based on a notional annual base salary of $406,900, and payments, if any, would have been made in USD. As explained in note 7 to the Summary Compensation Table, a portion of Mr. Thibaud’s salary is paid in Euros, and the amount of base salary reported in that table reflects fluctuations in the conversion rate between Euros and USD. These fluctuations are not taken into consideration in determining Mr. Thibaud’s target bonus or bonus payments.

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(1)	Securities underlying stock options are shares of our common stock.

(2)	These restricted share awards vest in three equal installments on each of the first three anniversaries of the grant date (August 15, 2016), contingent in each case on the executive remaining an employee as of each such date.

(3)

The fiscal 2017 annual performance-based restricted stock awards vest based on relative performance to our peer group for the three-year period ending June 30, 2019. The vesting formula for the fiscal 2017 annual performance-based restricted stock awards is as set forth in the tables below but with the following performance periods and weightings: (i) a ratio of adjusted EBITDA to revenue for the three-year period ending June 30, 2019, percentile ranked relative to our peer group (75% weighting); and (ii) revenue growth percentage for the three-year period ending June 30, 2019, percentile ranked relative to our peer group (25% weighting). As with the time-based awards, vesting for the performance awards is contingent in each case on the executive remaining an employee as of each vesting date.

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(4)	These restricted share awards vest in three equal installments on each of the first three anniversaries of the grant date (August 15, 2017), contingent in each case on the executive remaining an employee as of each such date.

(5)

The fiscal 2018 annual performance-based restricted stock awards vest based on relative performance to our peer group for the three-year period ending June 30, 2020. The vesting formula for the fiscal 2018 annual performance-based restricted stock awards is as set forth in the tables below but with the following performance periods and weightings: (i) a ratio of adjusted EBITDA to revenue for the three-year period ending June 30, 2020, percentile ranked relative to our peer group (75% weighting); and (ii) revenue growth percentage for the three-year period ending June 30, 2020, percentile ranked relative to our peer group (25% weighting). As with the time-based awards, vesting for the performance awards is contingent in each case on the executive remaining an employee as of each vesting date.

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(6)	These restricted share awards vest in three equal installments on each of the first three anniversaries of the grant date (August 15, 2018), contingent in each case on the executive remaining an employee as of each such date.

(7)

The fiscal 2019 annual performance-based restricted stock awards vest based on relative performance to our peer group for the three-year period ending June 30, 2021. The vesting formula for the fiscal 2019 annual performance-based restricted stock awards is as set forth in the tables below but with the following performance periods and weightings: (i) a ratio of adjusted EBITDA to revenue for the three-year period ending June 30, 2021, percentile ranked relative to our peer group (75% weighting); and (ii) revenue growth percentage for the three-year period ending June 30, 2021, percentile ranked relative to our peer group (25% weighting). As with the time-based awards, vesting for the performance awards is contingent in each case on the executive remaining an employee as of each vesting date.

(8)

Mr. Cambria joined the Company in August 2016 and his equity grant reflects a new hire grant. His new hire performance-based restricted stock awards vest based on relative performance to our peer group for the three-year period ending June 30, 2019. The vesting formula for the fiscal 2017 new hire performance-based restricted stock awards is as set forth in the tables below but with the following performance periods and weightings: (i) a ratio of adjusted EBITDA to revenue for the three-year period ending June 30, 2019, percentile ranked relative to our peer group (75% weighting); and (ii) revenue growth percentage for the three-year period ending June 30, 2019, percentile ranked relative to our peer group (25% weighting). As with the time-based awards, vesting for the performance awards is contingent in each case on the executive remaining an employee as of each vesting date.

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(9)	These restricted share awards vest in three equal installments on each of the first three anniversaries of the grant date (February 15, 2018), contingent in each case on the executive remaining an employee as of each such date.

(10)

Mr. Ruppert was appointed as Executive Vice President, Chief Financial Officer, and Treasurer in February 2018. His promotion performance-based restricted stock awards vest based on relative performance to our peer group for the three-year period ending December 31, 2020. The vesting formula for these promotion performance-based restricted stock awards is as set forth in the tables below but with the following performance periods and weightings: (i) a ratio of adjusted EBITDA to revenue for the three-year period ending December 31, 2020, percentile ranked relative to our peer group (75% weighting); and (ii) revenue growth percentage for the three-year period ending December 31, 2020, percentile ranked relative to our peer group (25% weighting). As with the time-based awards, vesting for the performance awards is contingent in each case on the executive remaining an employee as of each vesting date.

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(1)	The actuarial present value of Mr. Thibaud’s pension benefit as of June 30, 2019 is calculated in Euros. The dollar amount set forth above reflects the exchange rate at June 30, 2019. The actuarial present value assumes a 1.3% discount rate and an age of retirement of 63 years.

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(1)	The value of health, dental, and vision insurance benefits is based on the type of coverage we carried for Mr. Aslett as of June 30, 2019, and the costs associated with such coverage on that date.

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(1)	The value of health, dental, and vision insurance benefits is based on the type of coverage we carried for the executive as of June 30, 2019, and the costs associated with such coverage on that date.

•	a lump sum cash payment equal to two times (2x) the sum of the CEO’s then current annualized base salary and bonus target under our annual executive bonus plan (excluding any over-achievement awards);

•	payment of the cost of providing the executive with outplacement services up to a maximum of $45,000; and

•	payment of the cost of providing the CEO with health and dental insurance up to 24 months following such termination on the same basis as though the CEO had remained an active employee.

•	In addition, if the CEO’s employment is terminated within 24 months after a change in control (or during a potential change in control period provided that a change in control takes place within 24 months thereafter), vesting of all his then outstanding stock options and other stock-based awards immediately accelerates and all such awards become exercisable or non-forfeitable.

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•	a lump sum cash payment equal to one and one-half times (1.5x) the sum of the executive’s then current annualized base salary and bonus target under our annual executive bonus plan (excluding any over-achievement awards);

•	payment of the cost of providing the executive with outplacement services up to a maximum of $45,000; and

•	payment of the cost of providing the executive with health and dental insurance up to 18 months following such termination on the same basis as though the executive had remained an active employee.

•	In addition, if the executive’s employment is terminated within 18 months after a change in control (or during a potential change in control period provided that a change in control takes place within 18 months thereafter), vesting of all his then outstanding stock options and other stock-based awards immediately accelerates and all such awards become exercisable or non-forfeitable.

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(1)

The amounts shown in this column represent the closing price of our common stock on the NASDAQ Global Select Market on June 28, 2019 ($70.35) multiplied by the number of restricted shares held by the executive as reflected in the Outstanding Equity Awards at Fiscal Year-End 2019 above. The maximum potential value of the restricted stock awards (assuming the highest level of performance achievement for the performance-based awards and the $70.35 closing price on June 30, 2019) that could be earned in a change in control was: Mr. Aslett – $22,110,302; Mr. Cambria – $7,639,588; Mr. Ruppert – $8,757,924; and Mr. Thibaud – $10,241,271.

(2)	The value of health and dental insurance benefits is based on the type of coverage we carried for the named executive officer as of June 30, 2019 and the costs associated with such coverage on such date.

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