# EDGAR Filing Document

**Accession Number:** 0001049521
**File Stem:** 0001049521-25-000070
**Filing Date:** 2025-11
**Character Count:** 27625
**Document Hash:** 3873a085bf5df560cef1c8d4efc0833c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001049521-25-000070.hdr.sgml**: 20251105

**ACCESSION NUMBER**: 0001049521-25-000070

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 18

**FILED AS OF DATE**: 20251105

**DATE AS OF CHANGE**: 20251105

**EFFECTIVENESS DATE**: 20251105

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MERCURY SYSTEMS INC
- **CENTRAL INDEX KEY:** 0001049521
- **STANDARD INDUSTRIAL CLASSIFICATION:** ELECTRONIC COMPONENTS & ACCESSORIES [3670]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 042741391
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0630

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-291284
- **FILM NUMBER:** 251453993

**BUSINESS ADDRESS:**
- **STREET 1:** 50 MINUTEMAN ROAD
- **CITY:** ANDOVER
- **STATE:** MA
- **ZIP:** 01810
- **BUSINESS PHONE:** 9782561300

**MAIL ADDRESS:**
- **STREET 1:** 50 MINUTEMAN ROAD
- **CITY:** ANDOVER
- **STATE:** MA
- **ZIP:** 01810

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MERCURY COMPUTER SYSTEMS INC
- **DATE OF NAME CHANGE:** 19971112

**As filed with the Securities and Exchange Commission on November 5, 2025**

**Registration No. 333- &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549** 

**FORM S-8**

**REGISTRATION STATEMENT**

***UNDER***

***THE SECURITIES ACT OF 1933***

**MERCURY SYSTEMS, INC.**

**(Exact Name of Registrant as Specified in its Charter)**

---

| | |
|:---|:---|
| **Massachusetts** | **04-2741391** |
| **(State or other jurisdiction of incorporation or organization)** | **(I.R.S. Employer Identification Number)** |
| **50 Minuteman Road** | |
| **Andover, Massachusetts** | **01810** |
| **(Address of Principal Executive Offices)** | **(Zip Code)** |

---

**MERCURY SYSTEMS, INC.**

**2025 Long Term Incentive Plan**

**(Full title of the plan)**

**Stuart H. Kupinsky**

**Executive Vice President, Chief Legal Officer, and Corporate Secretary** 

**Mercury Systems, Inc.**

**50 Minuteman Road**

**Andover, Massachusetts 01810**

**(Name and address of agent for service)**

**(978) 256-1300**

**(Telephone number, including area code, of agent for service)**

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 Exchange Act.

---

| | |
|:---|:---|
| Large accelerated filer [X] | Accelerated filer [] |
| Non-accelerated filer [] | Smaller reporting company [] |
|  | Emerging growth company [] |

---

<u>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 the Securities Act. [] <br></u>

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**EXPLANATORY NOTE**

This Registration Statement is being filed solely for the purpose of registering 1,900,000 shares of common stock, par value $0.01 per share (the "Common Stock"), of Mercury Systems, Inc. (the "Company") to be offered to participants under the Company's 2025 Long Term Incentive Plan ("LTIP").

**PART I**

**INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS**

**ITEMS 1 AND 2.**

The documents containing the information for the LTIP specified by Part I of this Registration Statement will be sent or given to the employees as specified by Rule 428(b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). Such documents need not be filed with the Securities and Exchange Commission (the "Commission") either as a part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 of the Securities Act. Such documents and the documents incorporated by reference pursuant to Item 3 of Part II of this Registration Statement, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.

**PART II**

**INFORMATION REQUIRED IN THE REGISTRATION STATEMENT**

**ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.**

The following documents are incorporated herein by reference:

(a) The Company's Annual Report on Form 10-K for the fiscal year ended June 27, 2025, as filed with the Commission on August 11, 2025;

(b) The Company's Definitive Proxy Statement on Schedule 14A, as filed with the Commission on September 10, 2025, to the extent specifically incorporated by reference into the Company's Annual Report on Form 10-K for the fiscal year ended June 27, 2025;

(c) The Company's Quarterly Report on Form 10-Q for the fiscal quarter ended September 26, 2025, as filed with the Commission on November 4, 2025; and

(d) The Company's Current Reports on Form 8-K filed with the Commission on October 28, 2025 and November 4, 2025 (Items 1.01, 2.03, and 8.01 only).

All reports and documents subsequently filed by the Company pursuant to Sections 13(a), 13(c), 14, and 15(d) of the Securities Exchange Act of 1934, as amended, prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or that deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part hereof from the date of the filing of such documents.

For the purposes of this Registration Statement, any statement contained herein or in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

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**ITEM 4. DESCRIPTION OF SECURITIES.**

Not applicable.

**ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.**

None.

**ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.**

Section 2.02(b)(4) of Chapter 156D of the Massachusetts General Laws allows a corporation to eliminate or limit the personal liability of a director of a corporation to the corporation or its shareholders for monetary damages for a breach of fiduciary duty as a director notwithstanding any provision of law imposing such liability, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of an improper distribution or obtained an improper personal benefit. The Company has included a similar provision in its articles of organization.

Section 8.51(a) of Chapter 156D of the Massachusetts General Laws provides that a corporation may indemnify its directors against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement reasonably incurred in connection with any litigation or other legal proceeding brought against any director by virtue of his position as a director of the corporation unless he is deemed to have not acted in good faith in the reasonable belief that his action was in the best interest of the corporation. As noted below, the Company has provided for director indemnification in its articles of organization and bylaws.

Section 8.52 of Chapter 156D of the Massachusetts General Laws provides that a corporation must indemnify a director who is wholly successful, on the merits or otherwise, in the defense of any proceeding to which the director was a party because he was a director of the corporation against reasonable expenses incurred by him in connection with the proceeding.

Section 8.56(a) of Chapter 156D of the Massachusetts General Laws ("Section 8.56") provides that a corporation may indemnify its officers to the same extent as its directors and, for officers that are not directors, to the extent provided by (i) the articles of organization, (ii) the bylaws, (iii) a vote of the board of directors or (iv) a contract. In all instances, the extent to which a corporation provides indemnification to its officers under Section 8.56 is optional. As noted below, the Company has provided for officer indemnification in its bylaws.

The Company's bylaws, as amended, provide that the Company shall indemnify its directors and the officers that have been appointed by the Board of Directors to the fullest extent permitted by law.

The Company maintains directors' and officers' liability insurance.

The Company has entered into indemnification agreements with its directors. The indemnification agreements require, among other matters, that the Company indemnify its directors to the fullest extent permitted by law and advance to directors certain expenses, subject to reimbursement if it is subsequently determined that indemnification is not permitted.

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**ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.**

None.

**ITEM 8. EXHIBITS.**

---

| | |
|:---|:---|
| Exhibit | Description |
| 4.1 | [Articles of Organization (incorporated herein by reference to Exhibit 3.1.1 of the Company's Annual Report on Form 10-K for the fiscal year ended June 30, 2009)](https://www.sec.gov/Archives/edgar/data/1049521/000119312509187696/dex311.htm) |
| 4.2 | [Articles of Amendment (incorporated herein by reference to Exhibit 3.1.2 of the Company's Annual Report on Form 10-K for the fiscal year ended June 30, 2010)](https://www.sec.gov/Archives/edgar/data/1049521/000119312510192991/dex312.htm) |
| 4.3 | [Articles of Amendment (incorporated herein by reference to Exhibit 1 of the Company's Registration Statement on Form 8-A filed with the Commission on December 15, 2005)](https://www.sec.gov/Archives/edgar/data/1049521/000119312505243468/dex1.htm) |
| 4.4 | [Articles of Amendment (incorporated herein by reference to Exhibit 3.1 of the Company's Current Report on Form 8-K filed with the Commission on November 13, 2012)](https://www.sec.gov/Archives/edgar/data/1049521/000119312512465660/d433286dex31.htm) |
| 4.5 | [Articles of Amendment (incorporated herein by reference to Exhibit 3.1 of the Company's Current Report on Form 8-K filed with the Commission on June 30, 2015)](https://www.sec.gov/Archives/edgar/data/1049521/000104952115000029/articlesofamendment.htm) |
| 4.6 | [Articles of Amendment (incorporated herein by reference to Exhibit 3.1 of the Company's Current Report on Form 8-K filed with the Commission on December 29, 2021)](https://www.sec.gov/Archives/edgar/data/1049521/000104952121000066/a2021122921articlesofame.htm) |
| 4.7 | [By-laws, amended and restated effective October 26, 2022 (incorporated herein by reference to Exhibit 3.1 of the Company's Current Report on Form 8-K filed with the Commission on October 28, 2022)](https://www.sec.gov/Archives/edgar/data/1049521/000104952122000053/a8-k2022102822exhibit31.htm) |
| 5.1\* | [Opinion of Dechert LLP](exhibit5opinionltipdeche.htm) |
| 23.1\* | [Consent of KPMG LLP](kpmgnovember2025consent.htm) |
| 23.2 | Consent of Dechert LLP (contained in the opinion filed as Exhibit 5.1 to this Registration Statement) |
| 24.1 | Power of Attorney (included in signature page to this Registration Statement) |
| 99.1 | [Mercury Systems, Inc. 2025 Long Term Incentive Plan (incorporated herein by reference to Appendix A to the Company's Definitive Proxy Statement on Schedule 14A filed on September 10, 2025)](https://www.sec.gov/Archives/edgar/data/1049521/000104952125000029/mrcy-20250910.htm) |
| 107\* | [Calculation of Filing Fee Table](exfilingfees.htm) |
| \* | Filed herewith |

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**ITEM 9. UNDERTAKINGS.**

(a) The Company hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the

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Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Filing Fee Table" in the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

*Provided, however*, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the registration statement is on Form S-8, and if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Company pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement;

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial *bona fide* offering thereof; and

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b) The Company hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Company's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial *bona fide* offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Company pursuant to the provisions described under Item 6 above, or otherwise, the Company has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Company of expenses incurred or paid by a director, officer or controlling person of the Company in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Company will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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**SIGNATURES**

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the Town of Andover, the Commonwealth of Massachusetts on this 5th day of November, 2025.

MERCURY SYSTEMS, INC.

By: <u>/s/ David E. Farnsworth</u>

David E. Farnsworth

Executive Vice President, Chief Financial Officer

**Power of Attorney**

KNOW ALL MEN BY THESE PRESENTS that each person whose signature appears below constitutes and appoints William L. Ballhaus, David E. Farnsworth, and Stuart H. Kupinsky as his or her true and lawful attorneys-in-fact and agents, each acting alone, with full powers of substitution and resubstitution, for him or her or in his or her name, place and stead, in any and all capacities to sign any and all amendments or post-effective amendments to this Registration Statement (or any Registration Statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933, as amended), and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, each acting alone, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, each acting alone, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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| | | |
|:---|:---|:---|
| Signature | Title | Date |
| <br><u>/s/ William L. Ballhaus</u><br>William L. Ballhaus | <br>President, Chief Executive Officer, and Chairman of the Board (Principal Executive Officer) | <br>November 5, 2025 |
| <br><u>/s/ David E. Farnsworth</u><br>David E. Farnsworth | <br>Executive Vice President, Chief Financial Officer (Principal Financial Officer) | <br>November 5, 2025 |
| <br><u>/s/ Douglas D. Munro</u><br>Douglas D. Munro | <br>Senior Vice President, Chief Accounting Officer (Principal Accounting Officer) | <br>November 5, 2025 |

---

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---

| | | |
|:---|:---|:---|
| <br><u>/s/ Jean Bua</u><br>Jean Bua | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Orlando P. Carvalho</u><br>Orlando P. Carvalho | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Gerard J. DeMuro</u><br>Gerard J. DeMuro | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Lisa S. Disbrow</u><br>Lisa S. Disbrow | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Howard L. Lance</u><br>Howard L. Lance | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Scott Ostfeld</u><br>Scott Ostfeld | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Barry R. Nearhos</u><br>Barry R. Nearhos | <br>Director | <br>November 5, 2025 |
| <br><u>/s/ Debora A. Plunkett</u><br>Debora A. Plunkett | <br>Director | <br>November 5, 2025 |

---

## Ex-Filing

?xml version='1.0' encoding='ASCII'? exfilingfees

**Exhibit 107**

**Calculation of Filing Fee Table**

**FORM S-8**

**(Form Type)**

**Mercury Systems, Inc.**

**(Exact Name of the Registrant as Specified in its Charter)**

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| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** | **Table 1: Newly Registered Securities** |
| **Security Type** | **Security Class Title** | **Fee Calculation Rule** | **Amount Registered**<br>**(1)** | **Proposed Maximum Offering Price Per Share (2)** | **Maximum<br>aggregate offering<br>price (2)** | **Fee Rate** | **Amount of registration fee** |
| Equity | Common stock, par value $0.01 per share | Other | 1900000 | $78.085 | $148361500 | 0.0001381 | $20488.72 |
| **Total Offering Amounts** | **Total Offering Amounts** | **Total Offering Amounts** | **Total Offering Amounts** | **Total Offering Amounts** | $148361500 | 0.0001381 | $20488.72 |
| **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | $0.00 |
| **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | $20488.72 |

---

(1) Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement on Form S-8 also covers an indeterminate number of additional shares of Common Stock to be offered or sold as a result of the anti-dilution provisions of the Mercury Systems, Inc. 2025 Long term Incentive Plan, including to prevent dilution resulting from any reorganization, recapitalization, reclassification, stock dividend, stock split, or other similar change.

(2) Calculated in accordance with Rule 457(c) and (h) under the Securities Act solely for the purpose of determining the amount of the registration fee, based on the average of the high and low prices of our Common Stock on the Nasdaq Global Select Market on October 31, 2025.

## Exhibit 5.1

![](exhibit5opinionltipdeche001.jpg)

Dechert LLP Three Bryant Park 1095 Avenue of the Americas New York, NY 10036-6797 +1 212 698 3500 Main +1 212 698 3599 Fax BUSINESS.33715119.2 November 5, 2025 Mercury Systems, Inc. 50 Minuteman Road Andover, MA 01810 Re: REGISTRATION STATEMENT ON FORM S-8 Ladies and Gentlemen: We have acted as counsel to Mercury Systems, Inc., a Massachusetts corporation (the "Company"), in connection with the filing with the U.S. Securities and Exchange Commission (the "Commission") of a registration statement on Form S-8 (the "Registration Statement") for the purpose of registering under the Securities Act of 1933, as amended (the "Securities Act"), 1,900,000 shares of its common stock, par value $0.01 per share (the "Shares"), issuable under the Company's 2025 Long Term Incentive Plan (the "LTIP"). This opinion is being furnished to the Company in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement other than as expressly stated herein with respect to the Shares. As the Company's counsel, we have examined such documents and such matters of fact and law that we have deemed necessary for the purpose of rendering the opinion expressed herein. In our examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as original documents, and the conformity to original documents of all documents submitted to us as copies, the legal capacity of natural persons who are signatories to the documents examined by us, and the legal power and authority of all persons signing on behalf of parties to all documents. We have further assumed, without independent investigation or verification, the accuracy and completeness of all corporate records made available to us by the Company and that there has been no oral modification of, or amendment or supplement (including any express or implied waiver, however arising) to, any of the documents used by us to form the basis of our opinion expressed herein. In rendering our opinion expressed herein, we have assumed that (i) prior to the issuance of any of the Shares, there will exist under the Company's Restated Articles of Organization the requisite number of authorized but unissued shares of common stock; (ii) the resolutions authorizing the Company to issue the Shares in accordance with the terms and conditions of the LTIP will remain in effect and unchanged at all times during which the Shares are issued by the Company; and (iii) the Registration Statement, and any amendments thereto, will be, and will continue to be, effective. Subject to the foregoing and the other matters set forth herein, it is our opinion that, as of the date hereof, when the Shares shall have been duly registered on the books of the transfer agent and registrar therefor in the name or on behalf of the holders and have been issued by the Company against payment therefor (not less than par value) in the circumstances contemplated by the LTIP, assuming in each case that the individual issuances, grants or awards under the LTIP are duly authorized by all necessary corporate action and duly issued, granted or awarded and exercised in accordance with the requirements of law and the LTIP (and the

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![](exhibit5opinionltipdeche002.jpg)

Mercury Systems, Inc. November 5, 2025 Page 2 BUSINESS.33715119.2 / agreements and awards duly adopted thereunder and in accordance therewith), the issue and sale of the Shares will have been duly authorized by all necessary corporate action of the Company, and the Shares will be validly issued, fully paid and non-assessable. This opinion has been prepared, and should be interpreted, in accordance with customary practice followed in the preparation of opinion letters by lawyers who regularly give, and such customary practice followed by lawyers who on behalf of their clients regularly advise opinion recipients regarding, opinion letters of this kind. The opinion expressed herein is based upon the law as in effect and the documentation and facts known to us on the date hereof. We have not undertaken to advise the Company or any other person of any subsequent changes in the law or of any facts that hereafter may come to our attention. We are members of the Bar of the Commonwealth of Massachusetts, and the foregoing opinion is limited to the Business Corporation Act of the Commonwealth of Massachusetts. We hereby consent to the filing of this opinion as an exhibit to the Registration Statement. In giving this consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder. We do not consider that we are "experts" within the meaning of such term as used in the Securities Act, or the rules and regulations of the Securities and Exchange Commission issued thereunder, with respect to any part of the Registration Statement, including this opinion as an exhibit or otherwise. Very truly yours, /s/ DECHERT LLP

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![](exhibit5opinionltipdeche003.jpg)

Mercury Systems, Inc. November 5, 2025 Page 3

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## Exhibit 23.1

![](kpmgnovember2025consent001.jpg)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;KPMG LLP Two Financial Center 60 South Street Boston, MA 02111 KPMG LLP, a Delaware limited liability partnership and a member firm of the KPMG global organization of independent member firms affiliated with KPMG International Limited, a private English company limited by guarantee. Consent of Independent Registered Public Accounting Firm We consent to the use of our report dated August 11, 2025, with respect to the consolidated financial statements of Mercury Systems, Inc. and subsidiaries, and the effectiveness of internal control over financial reporting, incorporated herein by reference. Boston, Massachusetts November 4, 2025

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