Exhibit 4.1

LEIDOS, INC.

Officers’ Certificate

March 2, 2026

Reference is made to the Indenture, dated as of October 8, 2020 (the “Indenture”), by and between Leidos, Inc. (the “Issuer”), Leidos Holdings, Inc., the Issuer’s parent company (the “Guarantor”) and Citibank, N.A., as trustee (the “Trustee”). The Trustee is the trustee for any and all securities issued under the Indenture. Pursuant to Section 2.01 and Section 3.01 of the Indenture, the undersigned officers do hereby certify, in connection with the issuance of $600,000,000 aggregate principal amount of 4.100% Notes due 2029 (the “2029 Notes”) and $800,000,000 aggregate principal amount of 5.000% Notes due 2036 (the “2036 Notes” and, together with the 2029 Notes, the “Notes”), that the terms of the Notes are as follows:

Capitalized terms used but not otherwise defined herein shall have the meanings specified in the Indenture.


Title		4.100% Notes due 2029 5.000% Notes due 2036

Issuer		Leidos, Inc.

Guarantor		Leidos Holdings, Inc.

Trustee, Registrar, Transfer Agent and Paying Agent		Citibank, N.A.

Aggregate Principal Amount at Maturity		$600,000,000 for the 2029 Notes $800,000,000 for the 2036 Notes

Maturity Date		March 15, 2029 for the 2029 Notes March 15, 2036 for the 2036 Notes

Interest		4.100% per annum for the 2029 Notes 5.000% per annum for the 2036 Notes

Date from which Interest will Accrue		March 2, 2026

Interest Payment Dates		March 15 and September 15, commencing on September 15, 2026

Interest Record Dates		March 1 and September 1

Guarantee		Leidos Holdings, Inc., the Issuer’s parent company, will fully and unconditionally guarantee the Notes, including the payment of principal, premium, if any, and interest. The guarantee will rank equally with all other general unsubordinated obligations of the Guarantor.



Special Mandatory Redemption		If (i) the Entrust Acquisition (as defined in the Notes) is not consummated on or before the later of (x) August 14, 2026 (the “End Date”) and (y) the date that is five Business Days after any later date to which the End Date may be extended in the Acquisition Agreement (as defined in the Notes) or (ii) the Issuer notifies the Trustee under the indenture that it will not pursue the consummation of the Entrust Acquisition, then the Issuer will be required to redeem the Notes, in whole, at a special mandatory redemption price equal to 101% of the aggregate principal amount of the Notes being redeemed, plus accrued and unpaid interest, if any, to, but excluding, the date upon which the Notes will be redeemed.

Optional Redemption		Prior to the applicable Par Call Date, at a redemption price equal to the greater of (i) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date (assuming the applicable series of Notes matured on the applicable Par Call Date) at the Treasury Rate + 10 basis points for the 2029 Notes and the Treasury Rate + 15 basis points for the 2036 Notes and (ii) 100% of the principal amount of the applicable series of Notes to be redeemed. On and after the applicable Par Call Date, at a redemption price equal to 100% of the principal amount of the Notes of such series to be redeemed. “Par Call Date” means February 15, 2029 in the case of the 2029 Notes and December 15, 2035 in the case of the 2036 Notes.



Repurchase upon a Change of Control		Upon the occurrence of a Change of Control Triggering Event (as defined in the applicable form of Notes attached hereto as Exhibits A-1 and A-2), the Issuer will be required to make an offer to purchase the applicable series of Notes at a price equal to 101% of their principal amount plus accrued and unpaid interest to the date of repurchase.

Conversion		None.

Sinking Fund		None.

Denominations		$2,000 and multiples of $1,000 thereafter.

Depositary		The Notes shall be issued as a global security with the Depositary Trust Company (“DTC”) as the Depositary. The Notes shall be registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC.

Permitted Liens		Clause (10) of the definition of “Permitted Liens” in the Indenture is hereby amended to read as follows: (10) Liens associated with a sale or discount of the accounts receivable of an Obligor, provided that such Lien (a) does not involve the creation of a Lien or negative pledge on any accounts receivable not so sold or discounted and (b) does not involve in the aggregate the sale or discount of accounts receivable having a book value exceeding $400,000,000

Miscellaneous		The terms of the Notes shall include such other terms as are set forth in the applicable form of Notes attached hereto as Exhibit A-1 and A-2 and in the Indenture.

Subject to the representations, warranties and covenants described in the Indenture, as amended or supplemented from time to time, the Issuer shall be entitled, subject to authorization by the Board of Directors of the Issuer and an Officers’ Certificate, to issue additional notes from time to time under each series of notes issued hereby. Any such additional notes of a series shall have identical terms as the applicable series of Notes, issued on the issue date, other than with respect to the date of issuance and the issue price (together, the “Additional Notes”). Any Additional Notes will be issued in accordance with Section 3.01 of the Indenture and the provisions set forth in the Appendix.

Such officer has read and understands the provisions of the Indenture and the definitions relating thereto. The statements made in this Officers’ Certificate are based upon the examination of the provisions of the Indenture and upon the relevant books and records of the Issuer. In such officer’s opinion, such officer has made such examination or investigation as is necessary to enable such officer to express an informed opinion as to whether or not the covenants and conditions of such Indenture relating to the issuance and authentication of the Notes have been complied with. In such officer’s opinion, such covenants and conditions have been complied with.

[Signature Page Follows]

IN WITNESS WHEREOF, the undersigned officers of the Issuer have duly executed this certificate as of the date first set forth above.


LEIDOS, INC.

By:		/s/ Christopher R. Cage
		Name: Christopher R. Cage
		Title: Executive Vice President and Chief Financial Officer

By:		/s/ J. Councill Leak
		Name: J. Councill Leak
		Title: Senior Vice President and Treasurer

[Signature Page to Officers’ Certificate Creating the Notes]

Exhibit A-1

THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAYBE REQUIRED PURSUANT TO SECTION 305 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 305 OF THE INDENTURE, (III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT TO SECTION 310 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

LEIDOS, INC.

4.100% Notes due 2029

No. R-[ ]

CUSIP No.: 52532X AM7
ISIN No.: US52532XAM74

$[ ]

LEIDOS, INC., a Delaware corporation (the “Issuer”), for value received promises to pay to CEDE & CO. or registered assigns the principal sum of [ ] on March 15, 2029.

Interest Payment Dates: March 15 and September 15 (each, an “Interest Payment Date”), commencing on September 15, 2026.

Interest Record Dates: March 1 and September 1 (each, an “Interest Record Date”).

Reference is made to the further provisions of this Note contained herein, which will for all purposes have the same effect as if set forth at this place.

IN WITNESS WHEREOF, the Issuer has caused this Note to be signed manually or by facsimile by its duly authorized officer.


LEIDOS, INC.

By:
		Name:
		Title:

[Company Signature Page to 2029 Global Note No. R-[ ]]

This is one of the Notes of the series designated herein and referred to in the within-mentioned Indenture,

Dated: March 2, 2026


CITIBANK, N.A., as Trustee

By:
		Name:
		Title:

[Signature Page to 2029 Global Note No. R-[ ]]

Leidos Holdings, Inc. (“Holdings” or the “Guarantor”) unconditionally guarantees, to the extent set forth in the Indenture and subject to the provisions of the Indenture, the due and punctual payment of the principal of, any premium and interest on the Notes, when and as the same shall become due and payable, whether at maturity, redemption, repayment or otherwise, and the other obligations set forth in, and all in accordance with the terms of Article Thirteen of the Indenture.

The obligations of the undersigned to the Holders of the Notes and to the Trustee pursuant to this Guarantee and in the Indenture are expressly set forth in the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee and all of the other provisions of the Indenture to which this Guarantee relates.

IN WITNESS WHEREOF, the Guarantor has caused this Note to be signed manually or by facsimile by its duly authorized officer.


LEIDOS HOLDINGS, INC.

By:
		Name:
		Title:

[Guarantor Signature Page to 2029 Global Note No. R-[ ]]

(REVERSE OF NOTE)

LEIDOS, INC.

4.100% Notes due 2029

1. Interest

LEIDOS, Inc. (the “Issuer”) promises to pay interest on the principal amount of this Note at the rate per annum described above. Cash interest on the Notes will accrue from the most recent date to which interest has been paid; or, if no interest has been paid, from March 2, 2026. Interest on this Note will be paid to but excluding the relevant Interest Payment Date. The Issuer will pay interest semi-annually in arrears on each Interest Payment Date, commencing September 15, 2026. Interest will be computed on the basis of a 360-day year consisting of twelve 30-day months in a manner consistent with Rule 11620(b) of the NASD Uniform Practice Code.

The Issuer shall pay interest on overdue principal from time to time on demand at the rate borne by the Notes and on overdue installments of interest (without regard to any applicable grace periods) to the extent lawful.

2. Paying Agent.

Initially, Citibank, N.A. (the “Trustee”) will act as paying agent. The Issuer may change any paying agent without notice to the Holders.

3. Indenture; Defined Terms.

This Note is one of the 4.100% Notes due 2029 (the “Notes”) issued under an indenture dated as of October 8, 2020 (the “Base Indenture”) by and between the Issuer, Leidos Holdings, Inc. (the “Guarantor”) and the Trustee, and established pursuant to an Officers’ Certificate dated March 2, 2026, issued pursuant to Section 2.01 and Section 3.01 thereof (together, the “Indenture”). This Note is a “Security” and the Notes are “Securities” under the Indenture.

For purposes of this Note, unless otherwise defined herein, capitalized terms herein are used as defined in the Indenture. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939 (15 U.S.C. Sections 77aaa-77bbbb) (the “TIA”) as in effect on the date on which the Indenture was qualified under the TIA. Notwithstanding anything to the contrary herein, the Notes are subject to all such terms, and Holders of Notes are referred to the Indenture and the TIA for a statement of them. To the extent the terms of the Indenture and this Note are inconsistent, the terms of the Indenture shall govern.

4. Guarantee.

The Guarantor has irrevocably, fully and unconditionally guaranteed, on an unsecured and unsubordinated basis, the full and punctual payment (whether at maturity, upon redemption or otherwise) of the principal of and interest on, and all other amounts payable under, the Notes and the full and punctual payment of all other amounts payable by the Issuer under the Indenture and any other obligations of the Issuer under the Indenture, subject to certain terms and conditions set forth in the Indenture.

5. Denominations; Transfer; Exchange.

The Notes are in registered form, without coupons, in denominations of $2,000 and multiples of $1,000 thereafter. A Holder shall register the transfer or exchange of Notes in accordance with the Indenture. The Issuer may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay certain transfer taxes or similar governmental charges payable in connection therewith as permitted by the Indenture. The Issuer need not issue, authenticate, register the transfer of or exchange any Notes or portions thereof for a period of fifteen (15) days before the mailing of a notice of redemption, nor need the Issuer register the transfer or exchange of any Note selected for redemption in whole or in part.

6. Amendment; Supplement; Waiver.

Subject to certain exceptions, the Notes and the provisions of the Indenture relating to the Notes may be amended or supplemented and any existing default or Event of Default or compliance with certain provisions may be waived with the written consent of the Holders of at least a majority in aggregate principal amount of all of the outstanding Notes. Without notice to or consent of any Holder, the parties thereto may amend or supplement the Indenture and the Notes to, among other things, cure any ambiguity, defect or inconsistency or comply with any requirements of the Commission in connection with the qualification of the Indenture under the TIA, or make any other change that does not adversely affect the rights of any Holder of a Note in any material respect.

8. Redemption.

Prior to February 15, 2029 (the “Par Call Date”), the Issuer may redeem the Notes at its option, in whole or in part at any time, or from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

(i)

(a) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date (assuming the Notes matured on the Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate (as defined below), plus 10 basis points less (b) interest accrued to the date of redemption; and

(ii)

100% of the principal amount of the Notes to be redeemed; and

plus, in each case, accrued interest thereon to the date of redemption.

Notwithstanding the foregoing, installments of interest on Notes that are due and payable on Interest Payment Dates falling on or prior to a redemption date will be payable on the Interest Payment Date to the registered Holders as of the close of business on the relevant Interest Record Date according to the Notes and the Indenture. The Trustee shall have no obligation to calculate or verify any calculation of a redemption price.

On or after the Par Call Date, the Issuer may redeem the Notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest thereon to the redemption date.

“Treasury Rate” means, with respect to any redemption date, the yield determined by Leidos in accordance with the following two paragraphs.

The Treasury Rate shall be determined by the Issuer after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third Business Day preceding the redemption date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily)—H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S. government securities–Treasury constant maturities–Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, the Issuer shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields—one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life—and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date.

If on the third Business Day preceding the redemption date H.15 TCM is no longer published, the Issuer shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second Business Day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, the Issuer shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, the Issuer shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places. The Trustee shall have no obligation to calculate or verify the redemption price on the Notes.

The Issuer’s actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Notice of any redemption will be mailed or electronically delivered (or otherwise transmitted in accordance with the depositary’s procedures) at least 10 days but not more than 60 days before the redemption date to each Holder of Notes to be redeemed (with a copy to the Trustee), except that redemption notices may be delivered more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction and discharge of the Indenture.

In the case of a partial redemption, selection of the Notes for redemption will be made pro rata, by lot or by such other method as the Trustee in its sole discretion deems appropriate and fair. No Notes of a principal amount of $2,000 or less will be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption that relates to the Note will state any conditions applicable to the redemption and the portion of the principal amount of the Note to be redeemed. A new Note in a principal amount equal to the unredeemed portion of the Note will be issued in the name of the Holder of the Note upon surrender for cancellation of the original Note. For so long as the Notes are held by DTC, Euroclear, Clearstream (or another Depositary), the redemption of the Notes shall be done in accordance with the policies and procedures of the Depositary.

Unless the Issuer defaults in payment of the redemption price, on and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption.

9. Special Mandatory Redemption.

If (i) the Entrust Acquisition is not consummated on or before the later of (x) August 14, 2026 (the “End Date”) and (y) the date that is five Business Days after any later date to which the End Date may be extended in the Acquisition Agreement (such later date, the “Special Mandatory Redemption End Date”) or (ii) the Issuer notifies the Trustee under the Indenture that it will not pursue the consummation of the Entrust Acquisition (the earlier of the date of delivery of such notice described in this clause (ii) and the Special Mandatory Redemption End Date, a “Special Mandatory Redemption Trigger”), then the Issuer will be required to redeem the Notes (the “Special Mandatory Redemption”), in whole, at a special mandatory redemption price equal to 101% of the aggregate principal amount of the Notes being redeemed, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (as defined herein) (subject to the right of holders of the Notes of record on the relevant Interest Record Date to receive interest due on an Interest Payment Date falling prior to the Special Mandatory Redemption Date) (the “Special Mandatory Redemption Price”). Unless the Issuer defaults in payment of the Special Mandatory Redemption Price, on and after such Special Mandatory Redemption Date, interest will cease to accrue on the Notes to be redeemed.

In the event that the Issuer becomes obligated to redeem the Notes pursuant to the Special Mandatory Redemption, it will promptly, and in any event not more than five Business Days after the Special Mandatory Redemption Trigger, deliver notice to the Trustee of the Special Mandatory Redemption and the date upon which the Notes will be redeemed (the “Special Mandatory Redemption Date”), which date shall be no later than the tenth Business Day following the date of such notice unless some longer minimum period may be required by DTC (or any successor depositary), together with a notice of Special Mandatory Redemption for the Trustee to deliver to each registered holder of Notes. At the Company’s request in an Officers’ Certificate delivered to the Trustee at least

two (2) Business Days prior to the requested date of delivery, the Trustee will mail or deliver electronically if such Notes are held by any depositary (including, without limitation, DTC) in accordance with such depositary’s customary procedures, such notice of Special Mandatory Redemption to each registered holder of the Notes to be redeemed at its registered address.

On or before the Special Mandatory Redemption Date, the Issuer will pay to a paying agent for payment to each holder of the Notes the Special Mandatory Redemption Price.

Failure to make the Special Mandatory Redemption, if required in accordance with the terms described above, will constitute an Event of Default with respect to the Notes.

Upon the consummation of the Entrust Acquisition, the foregoing provisions regarding Special Mandatory Redemption will cease to apply.

For purposes of the foregoing discussion, the following definitions apply:

“Entrust Acquisition” means the proposed acquisition of all of the issued and outstanding shares of capital stock of KENE Parent, Inc. pursuant to the Acquisition Agreement.

“Acquisition Agreement” means the Stock Purchase Agreement, dated January 23, 2026, by and among Leidos, Inc., a wholly-owned subsidiary of Leidos Holdings, Inc., KENE Holdings, L.P. and KENE Parent, Inc., as may be amended or modified or any provision thereof waived.

10. Offer to Repurchase Upon Change of Control Triggering Event.

If a Change of Control Triggering Event (as defined below) occurs with respect to the Notes, unless the Issuer shall have exercised its right to redeem the Notes as described above, the Issuer shall be required to make an offer to each Holder of Notes to purchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that Holder’s Notes at a purchase price in cash equal to 101% of the aggregate principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of Holders of record on the relevant record date to receive interest due on the relevant Interest Payment Date); provided that after giving effect to the purchase, any Notes that remain outstanding shall have a denomination of $2,000 and integral multiples of $1,000 above that amount.

Within 30 days following the date upon which the Change of Control Triggering Event has occurred or, at the Issuer’s option, prior to any Change of Control (as defined below), but after the public announcement of the transaction that constitutes or may constitute the Change of Control, except to the extent that the Issuer shall have exercised its right to redeem the Notes pursuant to Section 8 hereof, the Issuer shall deliver a notice (a “Change of Control Offer”) to each Holder of Notes with a copy to the Trustee describing the transaction or transactions that constitute or may constitute a Change of Control Triggering Event and offering to purchase Notes on the date specified in the notice, which date will be no earlier than 10 days nor later than 60 days from the date such notice is delivered (other than as may be required by law) (such date, the “Change of Control Payment Date”). The notice will, if delivered prior to the date of consummation of the Change of Control, state that the Change of Control Offer is conditioned on the Change of Control being consummated on or prior to the Change of Control Payment Date specified in the notice.

On each Change of Control Payment Date, the Issuer shall, to the extent lawful:

•

accept for payment all Notes or portions of the Notes properly tendered pursuant to the applicable Change of Control Offer;

•

deposit with the paying agent an amount equal to the change of control payment in respect of all Notes or portions of Notes properly tendered pursuant to the applicable Change of Control Offer; and

•

deliver or cause to be delivered to the Trustee the Notes properly accepted together with an Officers’ Certificate stating the aggregate principal amount of Notes or portions of Notes being purchased.

The paying agent will promptly deliver, to each Holder of Notes so tendered the payment for such Notes, and the Trustee shall promptly authenticate and deliver (or cause to be transferred by book entry) to each holder a new Note equal in principal amount to any unpurchased portion of the Notes surrendered, if any.

The Issuer shall comply, to the extent applicable, with the requirements of Rule 14(e)-1 of the Exchange Act and any other securities laws or regulations in connection with the purchase of Notes pursuant to a Change of Control Triggering Event. To the extent that the provisions of any securities laws or regulations conflict with the terms described in the Notes, the Issuer shall comply with the applicable securities laws and regulations and shall not be deemed to have breached its obligations by virtue thereof.

Holders of Notes electing to have Notes purchased pursuant to a Change of Control Offer will be required to surrender their Notes, with the form entitled “Repurchase Exercise Notice Upon a Change of Control” on the reverse of the Note completed, to the paying agent at the address specified in the notice, or transfer their Notes to the paying agent by book-entry transfer pursuant to the applicable procedures of the paying agent, prior to the close of business on the third business day prior to the Change of Control Payment Date.

The Issuer shall not be required to make a Change of Control Offer with respect to the Notes if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by the Issuer and such third party purchases all Notes properly tendered and not withdrawn under its offer.

In addition, the Issuer shall not purchase any Notes if there has occurred and is continuing on the Change of Control Payment Date an Event of Default under the Indenture, other than a default in the payment of the change of control payment upon a Change of Control Triggering Event.

If Holders of not less than 95% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in a Change of Control Offer and the Issuer, or any third party making a Change of Control Offer in lieu of the Issuer, as described above, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Issuer shall have the right, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase pursuant to the Change of Control Offer described above, to redeem all Notes that remain outstanding following such purchase at a redemption price in cash equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption (subject to the right of Holders of record on an Interest Record Date to receive interest on the relevant Interest Payment Date).

For purposes of the Change of Control Offer provisions of the Notes, the following definitions are applicable:

“Change of Control” means the occurrence of any one of the following:

•

the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the Issuer’s or the Guarantor’s assets and the assets of the Issuer’s subsidiaries taken as a whole to any “person” (as that term is used in Section 13(d)(3) of the Exchange Act) other than to the Issuer or one of its subsidiaries;

•

the consummation of any transaction (including without limitation, any merger or consolidation) the result of which is that any “person” (as that term is used in Section 13(d)(3) of the Exchange Act) becomes the “beneficial owner” (as defined in Rules 13d-3 and 13d-5 under the Exchange Act), directly or indirectly, of more than 50% of the Guarantor’s outstanding Voting Stock, measured by voting power rather than number of shares; or

•

the adoption of a plan relating to the Issuer’s liquidation or dissolution.

Notwithstanding the foregoing, a transaction will not be considered to be a Change of Control if (a) the Guarantor becomes a direct or indirect wholly owned subsidiary of a holding company and (b) immediately following that transaction, (1) the direct or indirect holders of the Voting Stock of the holding company are substantially the same as the holders of the Guarantor’s Voting Stock immediately prior to that transaction or (2) no person or group is the beneficial owner, directly or indirectly, of more than 50% of the total voting power of the Voting Stock of the holding company.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Ratings Event.

“Investment Grade” means a rating of Baa3 or better by Moody’s (or its equivalent under any successor rating category of Moody’s); a rating of BBB- or better by S&P (or its equivalent under any successor rating category of S&P); and the equivalent investment grade rating from any replacement Rating Agency or Agencies appointed by the Issuer.

“Moody’s” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

“Rating Agency” means each of Moody’s and S&P; provided, that if either of Moody’s or S&P ceases to rate the Notes or fails to make a rating of the Notes publicly available, the Issuer shall appoint a replacement for such Rating Agency that is a “nationally recognized statistical rating organization” within the meaning of Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act.

“Ratings Event” means the rating on the Notes is lowered by each of the Rating Agencies and such Notes are rated below an Investment Grade by each of the Rating Agencies on any day within the 60-day period (which 60-day period will be extended so long as the rating of the Notes is under publicly announced consideration for a possible downgrade by either of the Rating Agencies) after the earlier of (a) the occurrence of a Change of Control and (b) public notice of the occurrence of a Change of Control or the Issuer’s intention to effect a Change of Control; provided that a Ratings Event will not be deemed to have occurred in respect of a particular Change of Control (and thus will not be deemed a Ratings Event for purposes of the definition of Change of Control Triggering Event) if each Rating Agency making the reduction in rating does not publicly announce or confirm or inform the Trustee in writing at the Issuer’s request that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the Change of Control (whether or not the applicable Change of Control has occurred at the time of the Ratings Event). If any Rating Agency that provided a rating of a series of Notes on the day immediately prior to the beginning of such 60-day period (or extension thereof) is not providing a rating of such series of Notes at the end of such 60-day period (or extension thereof) for any reason, such 60-day period (or extension thereof) shall be extended an additional 30 days and, if the Issuer has not selected a replacement Rating Agency on or before the end of such 30-day period, then such Rating Agency shall be deemed to have lowered its rating of such series of Notes at the end of such 30- day period to be below an Investment Grade Rating. The Trustee shall have no obligation to monitor ratings on the Notes.

“S&P” means Standard & Poor’s Financial Services LLC, a division of S&P Global Inc., and its successors.

“Voting Stock” of any specified person as of any date means the capital stock of such person that is at the time entitled to vote generally in the election of the board of directors of such person.

10. Defaults and Remedies.

If an Event of Default (other than certain bankruptcy Events of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer) under the Indenture occurs with respect to the Notes and is continuing, then the Trustee may by notice to the Issuer or, the Holders of not less than 25% in aggregate principal amount of all of the outstanding Notes by notice in writing to the Issuer (and to the Trustee if given by Holders), require the Issuer to repay immediately the entire principal amount of all of the outstanding Securities of all series affected, together with all accrued and unpaid interest and premium, if any. If a bankruptcy Event of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer occurs and is continuing, then the entire principal amount of all of the outstanding Securities (including the Notes) will automatically become due immediately and payable without any declaration or other act on the part of the Trustee or any Holder. Holders of Notes may not enforce the Indenture, the Notes or related Guarantees except as provided in the Indenture. The Trustee is not obligated to enforce the Indenture, the Notes or related Guarantees unless it has received indemnity as it reasonably requires. The Indenture permits, subject to certain limitations therein provided, Holders of a majority in aggregate principal amount of all of the outstanding Notes to direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of Notes notice of certain continuing defaults or Events of Default if it determines that withholding notice is in their interest.

11. Authentication.

This Note shall not be valid until the Trustee manually signs the certificate of authentication on this Note.

12. Abbreviations and Defined Terms.

Customary abbreviations may be used in the name of a Holder of a Note or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

13. CUSIP Numbers.

Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Issuer has caused CUSIP numbers to be printed on the Notes as a convenience to the Holders of the Notes. No representation is made as to the accuracy of such numbers as printed on the Notes and reliance may be placed only on the other identification numbers printed hereon.

14. Governing Law.

The laws of the State of New York shall govern the Indenture, including the Guarantee, and this Note thereof.

ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

and irrevocably appoint agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for him.

Date: Your Signature:

Sign exactly as your name appears on the other side of this Note.

Signature:

Signature Guarantee:



Signature must be guaranteed				Signature

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Registrar in addition to, or in substitution for, STAMP, all in accordance with the United States Securities Exchange Act of 1934, as amended.

SCHEDULE OF EXCHANGES OF NOTES

The following exchanges of a part of this Global Note for Physical Notes or a part of another Global Note have been made:


Date of Exchange		Amount of decrease in principal amount of this Global Note		Amount of increase in principal amount of this Global Note		Principal amount of this Global Note following such decrease (or increase)		Signature of authorized officer of Trustee

REPURCHASE EXERCISE NOTICE UPON A CHANGE OF CONTROL

To: Leidos, Inc.

The undersigned registered owner of this Security hereby acknowledges receipt of a notice from Leidos, Inc. (the “Issuer”) as to the occurrence of a Change of Control Triggering Event with respect to the Issuer and hereby directs the Issuer to pay, or cause the Trustee to pay, an amount in cash equal to 101% of the aggregate principal amount of the Notes, or the portion thereof (which is a multiple of $1,000, provided that the remaining principal amount, if any, following such repurchase shall be at least $2,000 or a multiple of $1,000 in excess thereof) below designated, to be repurchased plus interest accrued to, but excluding, the repurchase date, except as provided in the Indenture.

Dated:

Signature

Principal amount to be repurchased (a multiple of $1,000):

Remaining principal amount following such repurchase:

(zero or at least $2,000 or a multiple of $1,000 in excess thereof)


By:
		Authorized Signatory

A-1

Exhibit A-2

LEIDOS, INC.

5.000% Notes due 2036

No. R-[ ]

CUSIP No.: 52532X AN5
ISIN No.: US52532XAN57

$[ ]

LEIDOS, INC., a Delaware corporation (the “Issuer”), for value received promises to pay to CEDE & CO. or registered assigns the principal sum of [ ] on March 15, 2036.

Interest Payment Dates: March 15 and September 15 (each, an “Interest Payment Date”), commencing on September 15, 2026.

Interest Record Dates: March 1 and September 1 (each, an “Interest Record Date”).

Reference is made to the further provisions of this Note contained herein, which will for all purposes have the same effect as if set forth at this place.

IN WITNESS WHEREOF, the Issuer has caused this Note to be signed manually or by facsimile by its duly authorized officer.


LEIDOS, INC.

By:
		Name:
		Title:

[Company Signature Page to 2036 Global Note No. R-[ ]]

This is one of the Notes of the series designated herein and referred to in the within-mentioned Indenture,

Dated: March 2, 2026


CITIBANK, N.A., as Trustee

By:
		Name:
		Title:

[Signature Page to 2036 Global Note No. R-[ ]]

IN WITNESS WHEREOF, the Guarantor has caused this Note to be signed manually or by facsimile by its duly authorized officer.


LEIDOS HOLDINGS, INC.

By:
		Name:
		Title:

[Guarantor Signature Page to 2036 Global Note No. R-[ ]]

(REVERSE OF NOTE)

LEIDOS, INC.

5.000% Notes due 2036

1. Interest

2. Paying Agent.

Initially, Citibank, N.A. (the “Trustee”) will act as paying agent. The Issuer may change any paying agent without notice to the Holders.

3. Indenture; Defined Terms.

This Note is one of the 5.000% Notes due 2036 (the “Notes”) issued under an indenture dated as of October 8, 2020 (the “Base Indenture”) by and between the Issuer, Leidos Holdings, Inc. (the “Guarantor”) and the Trustee, and established pursuant to an Officers’ Certificate dated March 2, 2026, issued pursuant to Section 2.01 and Section 3.01 thereof (together, the “Indenture”). This Note is a “Security” and the Notes are “Securities” under the Indenture.

4. Guarantee.

5. Denominations; Transfer; Exchange.

6. Amendment; Supplement; Waiver.

8. Redemption.

Prior to December 15, 2035 (the “Par Call Date”), the Issuer may redeem the Notes at its option, in whole or in part at any time, or from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

(iii)

(a) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date (assuming the Notes matured on the Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate (as defined below), plus 15 basis points less (b) interest accrued to the date of redemption; and

(iv)

100% of the principal amount of the Notes to be redeemed; and

plus, in each case, accrued interest thereon to the date of redemption.

“Treasury Rate” means, with respect to any redemption date, the yield determined by Leidos in accordance with the following two paragraphs.

The Issuer’s actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Unless the Issuer defaults in payment of the redemption price, on and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption.

9. Special Mandatory Redemption.

On or before the Special Mandatory Redemption Date, the Issuer will pay to a paying agent for payment to each holder of the Notes the Special Mandatory Redemption Price.

Failure to make the Special Mandatory Redemption, if required in accordance with the terms described above, will constitute an Event of Default with respect to the Notes.

Upon the consummation of the Entrust Acquisition, the foregoing provisions regarding Special Mandatory Redemption will cease to apply.

For purposes of the foregoing discussion, the following definitions apply:

“Entrust Acquisition” means the proposed acquisition of all of the issued and outstanding shares of capital stock of KENE Parent, Inc. pursuant to the Acquisition Agreement.

10. Offer to Repurchase Upon Change of Control Triggering Event.

On each Change of Control Payment Date, the Issuer shall, to the extent lawful:

•

accept for payment all Notes or portions of the Notes properly tendered pursuant to the applicable Change of Control Offer;

•

deposit with the paying agent an amount equal to the change of control payment in respect of all Notes or portions of Notes properly tendered pursuant to the applicable Change of Control Offer; and

•

For purposes of the Change of Control Offer provisions of the Notes, the following definitions are applicable:

“Change of Control” means the occurrence of any one of the following:

•

the adoption of a plan relating to the Issuer’s liquidation or dissolution.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Ratings Event.

“Moody’s” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

“S&P” means Standard & Poor’s Financial Services LLC, a division of S&P Global Inc., and its successors.

10. Defaults and Remedies.

11. Authentication.

This Note shall not be valid until the Trustee manually signs the certificate of authentication on this Note.

12. Abbreviations and Defined Terms.

13. CUSIP Numbers.

14. Governing Law.

The laws of the State of New York shall govern the Indenture, including the Guarantee, and this Note thereof.

ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

and irrevocably appoint agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for him.

Date: Your Signature:

Sign exactly as your name appears on the other side of this Note.

Signature:

Signature Guarantee:



Signature must be guaranteed				Signature

SCHEDULE OF EXCHANGES OF NOTES

The following exchanges of a part of this Global Note for Physical Notes or a part of another Global Note have been made:


Date of Exchange		Amount of decrease in principal amount of this Global Note		Amount of increase in principal amount of this Global Note		Principal amount of this Global Note following such decrease (or increase)		Signature of authorized officer of Trustee

REPURCHASE EXERCISE NOTICE UPON A CHANGE OF CONTROL

To: Leidos, Inc.

Dated:

Signature

Principal amount to be repurchased (a multiple of $1,000):

Remaining principal amount following such repurchase:

(zero or at least $2,000 or a multiple of $1,000 in excess thereof)


By:
		Authorized Signatory

A-1

Leidos Holdings, Inc. 8-K