Second Supplemental Indenture, dated as of March 22, 2024, among Lumen Technologies, Inc., as issuer, the guarantors party thereto and Computershare Trust Company, N.A., as successor to Wells Fargo Bank, National Association, as trustee and collateral agent, relating to Lumen Technologies, Inc.s 4.000% Senior Secured Notes due 2027

Exhibit 4.1

EXECUTION VERSION

SECOND SUPPLEMENTAL INDENTURE

SECOND SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”) dated as of March 22, 2024, among LUMEN TECHNOLOGIES, INC. (f/k/a CENTURYLINK, INC.), a Louisiana corporation (the “Issuer”) the guarantors listed on the signature pages hereto (the “Guarantors”) and Computershare Trust Company, N.A., as successor to WELLS FARGO BANK, NATIONAL ASSOCIATION, a national banking association, as trustee and collateral agent under the Indenture referred to below (the “Trustee”).

W I T N E S S E T H :

WHEREAS, the Issuer and the Guarantors party thereto have heretofore executed and delivered to the Trustee that certain Indenture, dated as of January 24, 2020 (as amended, restated, supplemented or otherwise modified from time to time prior to the date hereof, the “Indenture”; capitalized terms used but not defined herein having the meanings assigned thereto in the Indenture), providing for the issuance of its 4.000% Senior Secured Notes due 2027 (the “Notes”);

WHEREAS, Section 802 of the Indenture provides, among other things, that with the consent of the Holders of at least a majority in principal amount of the Notes then outstanding, and solely for purposes of the amendments set forth in Sections 2(c) and (d) hereof, the consent of the Holders of at least two-thirds in principal amount of the Notes then outstanding (collectively, the “Requisite Consents” and the holders thereof, the “Consenting Noteholders”), the Issuer, the Guarantors and the Trustee may enter into a supplemental indenture for the purpose of amending the Indenture; and

WHEREAS, the Issuer has received the Requisite Consents from the Holders of the Notes to make the amendments to the Indenture, as set forth in Section 2 hereof (the “Amendments”), in accordance with the terms and conditions of the Indenture and the Consent Solicitation Statement, dated as of March 8, 2024 (the “Consent Solicitation”).

NOW THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Issuer, the Guarantors and the Trustee mutually covenant and agree for the equal and ratable benefit of the holders of the Notes as follows:

1. CAPITALIZED TERMS. Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture, and the rules of construction contained in the Indenture will apply equally to this Supplemental Indenture.

2. AMENDMENTS.

a. The Indenture is hereby amended to add or amend and restate, as applicable, the following definitions:

b. The following provisions of the Indenture and all references thereto in the Indenture will be deleted in their entirety, and the Issuer, the Restricted Subsidiaries and the Guarantors shall be released from their respective obligations under the following provisions of the Indenture, provided that the section or article numbers, as applicable, will remain and the word “[Reserved]” shall replace the title thereto:

c. Pursuant to Section 1308(a)(iii) of the Indenture, the Indenture is hereby amended to release all Collateral from the Lien and security interest created by the Notes Collateral Documents to secure the Obligations and all rights in the applicable Collateral shall be automatically released from the Lien and security interest created by the Notes Collateral Documents to secure the Obligations. This Supplemental Indenture constitutes notice to the Trustee and Notes Collateral Agent.

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d. The Indenture is hereby amended to release all Guarantees that may be released in accordance with Section 802(9)(B).

e. Section 301 is hereby amended to add the following as the ultimate sentence thereof: “Notwithstanding anything to the contrary in this Indenture: (1) this Section 301 is for the benefit of the Issuer and shall be applicable to a transaction only at the Issuer’s express election (provided the requirements of this Section 301 are otherwise met); and (2) the Transactions were not implemented pursuant to this Section 301 and this Section 301 does not and will not apply to the Transactions.”

f. Article Ten is hereby amended to add the following as the ultimate sentence thereof: “Notwithstanding anything to the contrary in this Indenture: (1) this Article Ten is for the benefit of the Issuer and shall be applicable to a transaction only at the Issuer’s express election (provided the requirements of this Article Ten are otherwise met); and (2) the Transactions were not implemented pursuant to this Article Ten and this Article Ten does not and will not apply to the Transactions.”

g. Section 1002 is hereby amended and restated in its entirety as follows: “This Article Ten shall govern any redemption of the Securities pursuant to Section 1001; provided that this Article shall not preclude or apply to any other purchase, repurchase, and/or exchange of the Securities, which shall not be subject to this Article.”

h. Any of the terms or provisions present in the Notes that relate to any of the provisions of the Indenture as amended by this Supplemental Indenture shall also be amended, mutatis mutandis, so as to be consistent with the amendments made by this Supplemental Indenture; provided, for the avoidance of doubt, that such amendments shall be made only to the extent such amendments may be made with the consent of holders of the Requisite Consents.

i. The Indenture is hereby amended by deleting any definitions from the Indenture with respect to which references would be eliminated as a result of the amendments to the Indenture pursuant to clause (b) above; provided, for the avoidance of doubt, that such amendments shall be made only to the extent such amendments may be made with the consent of holders of the Requisite Consents.

j. The Indenture and the Notes are hereby amended by deleting all references in the Indenture and the Notes to those sections and subsections that are deleted as a result of the amendments made by this Supplemental Indenture; provided, for the avoidance of doubt, that such amendments shall be made only to the extent such amendments may be made with the consent of holders of the Requisite Consents.

k. None of the Issuer, the Restricted Subsidiaries, the Guarantors, the Trustee or other parties to or beneficiaries of the Indenture shall have any rights, obligations or liabilities under such sections or clauses deleted pursuant to clause (b) above and such sections or clauses shall not be considered in determining whether a Default or Event of Default has occurred or whether the Issuer, the Restricted Subsidiaries, the Guarantors or the Trustee have observed, performed or complied with the provisions of the Indenture.

3. WAIVER AND RELEASE. Upon the terms and subject to the conditions set forth in this Supplemental Indenture, and in reliance upon the representations, warranties and covenants of the Issuer and the Guarantors contained herein and the other Note Documents, effective as of the date hereof, each Consenting Noteholder and each person that becomes a Holder after the date hereof, on behalf of itself and its predecessors, successors, assigns, agents, subsidiaries (except in the case of any Consenting Lumen Tech Revolving Lender or Consenting Lumen Tech Term A/A-1 Lender (each as defined in Transaction Support Agreement) that is a bona fide commercial bank, any Consenting Lumen Tech Revolving Lender Trading Desk (as defined in the Transaction Support Agreement) or any other affiliate of a bona fide commercial bank), Affiliates (except in the case of any Consenting Lumen Tech Revolving Lender or Consenting Lumen Tech Term A/A-1 Lender (each as defined in Transaction Support Agreement) that is a bona fide commercial bank, any Consenting Lumen Tech Revolving Lender Trading Desk (as defined in the Transaction Support Agreement) or any other affiliate of a bona fide commercial bank), and representatives, and as Consenting Noteholders to the maximum extent that such Consenting Noteholders may act collectively hereunder and under the Indenture (including, without limitation, Article 8 and

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Section 513 thereof), on behalf of the Holders, hereby irrevocably and forever (i) waive any cause of action, including but not limited to any actual, if any, and alleged defaults, Defaults or Events of Default, or any other claims of breach under or in respect of any loan document, note document or similar term as used or defined in any credit agreement, indenture or other definitive document governing any Indebtedness of the Issuer, Level 3 Financing, Inc., (“Level 3”), Qwest Corporation (“QC”) or Qwest Capital Funding, Inc. or any of their respective Subsidiaries and existing immediately prior to the effective date of the Transaction Support Agreement (as defined below) (such existing Indebtedness, the “Existing Debt”) or any other security agreement or related document or agreement that can be waived as of the date hereof, together with any and all related consequences thereof, including without limitation any actual or purported acceleration, in each case of any Indebtedness of the Issuer, Level 3, QC and each of their Subsidiaries (the “Waiver”) and (ii) hereby supplement the Indenture to incorporate the terms of this Waiver.

4. NOTES DEEMED CONFORMED. The provisions of the Notes shall be deemed to be conformed to the Indenture as supplemented by this Supplemental Indenture and amended to the extent that the Notes are inconsistent with the Indenture as amended by this Supplemental Indenture.

5. OPINION OF COUNSEL AND OFFICERS’ CERTIFICATE. Concurrently with the execution and delivery of this Supplemental Indenture, the Issuer shall deliver to the Trustee an Opinion of Counsel and an Officers’ Certificate to the effect that the execution of the Supplemental Indenture is authorized or permitted by the Indenture and that all conditions precedent to the execution of such supplemental indenture have been fulfilled.

6. RATIFICATION OF INDENTURE; SUPPLEMENTAL INDENTURE PART OF INDENTURE. Except as expressly amended hereby, the Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes, and every holder of Notes heretofore or hereafter authenticated and delivered shall be bound hereby.

7. GOVERNING LAW. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

8. TRUSTEE. The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity, enforceability or sufficiency of this Supplemental Indenture, any provisions herein or in respect of the recitals contained herein, all of which recitals are made solely by the Issuer. All of the provisions contained in the Indenture as amended hereby in respect of the rights, privileges, protections, immunities, powers and duties of the Trustee shall be applicable in respect of this Supplemental Indenture as fully and with like force and effect as though set forth in full herein.

9. COUNTERPARTS. The parties may sign any number of copies of this Supplemental Indenture. This Supplemental Indenture (and to any document executed in connection with this Supplemental Indenture) shall be valid, binding, and enforceable against a party only when executed and delivered by an authorized individual on behalf of the party by means of (i) any electronic signature permitted by the federal Electronic Signatures in Global and National Commerce Act, state enactments of the Uniform Electronic Transactions Act, and/or any other relevant electronic signatures law, including relevant provisions of the UCC (collectively, “Signature Law”); (ii) an original manual signature; or (iii) a faxed, scanned, or photocopied manual signature. Each electronic signature or faxed, scanned, or photocopied manual signature shall for all purposes have the same validity, legal effect, and admissibility in evidence as an original manual signature. Each party hereto shall be entitled to conclusively rely upon, and shall have no liability with respect to, any faxed, scanned, or photocopied manual signature, or other electronic signature, of any party and shall have no duty to investigate, confirm or otherwise verify the validity or authenticity thereof. This Supplemental Indenture may be executed in any number of counterparts, each of which shall be deemed to be an original, but such counterparts shall, together, constitute one and the same instrument. For avoidance of doubt, original manual signatures shall be used for execution or indorsement of writings when required under the UCC or other Signature Law due to the character or intended character of the writings. Each signed copy shall be an original, but all of them together represent the same agreement. The exchange of copies of this Supplemental Indenture and of signature pages by facsimile, PDF or other electronic signature transmission shall constitute effective execution and delivery of this Supplemental Indenture as to the parties hereto and may be used in lieu of the original Supplemental Indenture for all purposes. Signatures of the parties hereto transmitted by facsimile, PDF or other electronic signature shall be deemed to be their original signatures for all purposes.

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10. EFFECT OF HEADINGS. The Section headings herein are for convenience only and shall not affect the construction thereof.

11. EFFECTIVENESS; REVOCATION. This Supplemental Indenture shall become effective and binding on the Issuer, the Guarantors, the Trustee and every Holder of the Notes heretofore or hereafter authenticated and delivered under the Indenture upon the execution and delivery by the parties of this Supplemental Indenture. Nothing in this Supplemental Indenture, express or implied, shall give to any Person, other than the parties hereto and their successors under the Indenture and the Holders of the Existing Notes, any benefit or any legal or equitable right, remedy or claim under the Indenture.

12. SEVERABILITY. To the extent permitted by applicable law, any provision of this Supplemental Indenture held to be invalid, illegal or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity, illegality or unenforceability without affecting the validity, legality and enforceability of the remaining provisions thereof; and the invalidity of a particular provision in a particular jurisdiction shall not invalidate such provision in any other jurisdiction. In the event any one or more of the provisions contained in this Supplemental Indenture or any waiver, amendment or modification to this Supplemental Indenture or other Note Document (or purported waiver, amendment, or modification) including pursuant to this Supplemental Indenture, should be held invalid, illegal, unenforceable or to be unauthorized under the terms of Section 802 of the Indenture, then:

(x) (i) such provisions, waivers, amendments or modifications (or purported waivers, amendments or modifications) shall be construed or deemed modified so as to be valid, legal, enforceable and authorized under the terms of Section 802 of the Indenture, as applicable, with an economic effect as close as possible to that of the invalid, illegal, unenforceable or unauthorized provisions, waivers, amendments or modifications, as applicable, and (ii) once construed or modified by clause (i), such provisions, waivers, amendments or modifications (or attempted waivers, amendments, or modifications) shall be deemed to have been operative ab initio,

(y) any such provision, waiver, amendment or modification (or purported waiver, amendment or modification) not capable of being modified or construed in accordance with the foregoing clause (x) shall automatically be considered without effect, and such provision, waiver, amendment or modification shall for all purposes be deemed to have never been implemented or occurred, as applicable, and

(z) after giving effect to each of the foregoing clauses (x) and (y), the validity, legality and enforceability of the remaining provisions or waivers, amendments or modifications, as applicable, contained herein and therein shall not in any way be affected or impaired thereby.

Notwithstanding any other provision of this Supplemental Indenture, if a court of competent jurisdiction, in a final and unstayed order, determines that the amendments contained herein or that any aspect of the Lumen Tech Unsecured Notes Transaction or the Lumen Tech Secured Exchange (each as defined in that certain Amended and Restated Transaction Support Agreement, dated as of January 22, 2024, among the Issuer, Level 3, QC and the creditors of the Issuer and Level 3 from time to time party thereto and the other entities party thereto, as amended, restated, amended and restated, supplemented or otherwise modified from time to time) (the “Transaction Support Agreement”) invalid for any reason, such determination shall not (directly or indirectly) constitute a default or breach of this Supplemental Indenture, the Indenture or any other Note Document.

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13. WAIVER, RELEASE AND DISCLAIMER.

(a) Subject to the occurrence of, and effective from and after, such time the Proposed Amendments (as defined in the Consent Solicitation) become effective and operative (the “Effective Time” and the date thereof, the “Effective Date”) and the consummation of the Transactions, in exchange for the cooperation with, participation in, and entering into the Transactions by the Consenting Noteholders and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Issuer and each Guarantor (on behalf of itself and each of its subsidiaries and Affiliates) hereby finally and forever releases and discharges the Other Released Parties¹ and their respective property, to the fullest extent permitted under applicable law, from any and all causes of action and any other claims, debts, obligations, duties, rights, suits, damages, actions, derivative claims, remedies, and liabilities whatsoever, whether known or unknown, foreseen or unforeseen, in law, at equity, or otherwise, sounding in tort, contract, or based on any other legal or equitable principle, including, without limitation, violation of any securities law (federal, state or foreign), misrepresentation (whether intended or negligent), breach of duty (including any duty of candor), or any domestic or foreign law similar to the foregoing, based in whole or in part upon any act or omission, transaction, or other occurrence or circumstance taking place, being omitted, existing or otherwise arising immediately prior to the Effective Date arising from, relating to, or in connection with the Notes under, and as defined in the Indenture and each of the Notes Documents, the Transactions, the negotiation, formulation, or preparation of this Supplemental Indenture, the Definitive Documents (as defined in the Transaction Support Agreement) or the related guarantees, security documents, agreements, amendments, instruments, or other documents, including those that the Issuer or the Guarantors, their respective subsidiaries or any holder of a claim against or interest in the such entities or any other entity could have been legally entitled to assert derivatively or on behalf of any other entity (collectively, the “Company Released Claims”). Further, subject to the occurrence of, and effective from and after, the Effective Date and the consummation of the Transactions, each of the Issuer and the Guarantors (on behalf of itself and each of its subsidiaries and Affiliates) hereby covenants and agrees not to, directly or indirectly, bring, maintain, or encourage any cause of action or other claim or proceeding against an Other Released Party relating to or arising out of any Company Released Claim. Each of the Issuer and the Guarantors (on behalf of itself and each of its subsidiaries and Affiliates) further stipulates and agrees with respect to all Claims², that, subject to the occurrence of, and effective from and after, the Effective Date and the consummation of the Transactions, it hereby waives, to the fullest extent permitted by applicable law, any and all provisions, rights, and benefits conferred by any applicable U.S. federal or state law, any foreign law, or any principle of common law, that would otherwise limit a release or discharge of any unknown Claims pursuant to this Section 13(a).

(b) Subject to the occurrence of, and effective from and after, the Effective Date and the consummation of the Transactions, in exchange for the cooperation with, participation in, and entering into the Transactions by the Issuer and/or the Guarantors and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, each Consenting Noteholder on behalf of itself and each of its predecessors, successors, assigns, agents, subsidiaries (except in the case of any Consenting Lumen Tech Revolving Lender or Consenting Lumen Tech Term A/A-1 Lender (each as defined in Transaction Support Agreement) that is a bona fide commercial bank, any Consenting Lumen Tech Revolving Lender Trading Desk (as defined in the Transaction Support Agreement) or any other affiliate of a bona fide commercial bank), Affiliates (except in the case of any Consenting Lumen Tech Revolving Lender or Consenting Lumen Tech Term A/A-1 Lender (each as defined in Transaction Support Agreement) that is a bona fide commercial bank, any Consenting Lumen Tech Revolving Lender Trading Desk (as

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defined in the Transaction Support Agreement) or any other affiliate of a bona fide commercial bank), and representatives, and to the maximum extent that the Consenting Holders can act collectively for the Holders under the Indenture, the Holders hereby finally and forever releases and discharges (i) the Company Released Parties and their respective property and (ii) the other Consenting Noteholders and their respective property, in each case to the fullest extent permitted under applicable law, from any and all causes of action and any other claims, debts, obligations, duties, rights, suits, damages, actions, derivative claims, remedies, and liabilities whatsoever, whether known or unknown, foreseen or unforeseen, in law, at equity, or otherwise, sounding in tort, contract, or based on any other legal or equitable principle, including, without limitation, violation of any securities law (federal, state or foreign), misrepresentation (whether intended or negligent), breach of duty (including any duty of candor), or any domestic or foreign law similar to the foregoing, based in whole or in part upon any act or omission, transaction, or other occurrence or circumstance taking place, being omitted, existing or otherwise arising immediately prior to the Effective Date arising from, relating to, or in connection with any indebtedness of the Issuer or its subsidiaries outstanding as of the date hereof (including, without limitation, all Existing Debt), the Notes issued under, and as defined in, the Indenture and each of the Notes Documents, the Transactions, the negotiation, formulation, or preparation of this Supplemental Indenture, the Definitive Documents (as defined in the Transaction Support Agreement) or the related guarantees, security documents, agreements, amendments, instruments, or other documents, including those that a Consenting Noteholder or any holder of a claim against or interest in the Consenting Noteholder or any other entity could have been legally entitled to assert derivatively or on behalf of any other entity, and including, without limitation, any claim based upon or alleging a breach, default, Event of Default, or failure to comply with any such agreement or document (collectively, the “Consenting Noteholder Released Claims” and, together with the Company Released Claims, the “Released Claims”). For the avoidance of doubt, the Consenting Noteholder Released Claims encompass and include any and all claims or causes of action relating to or challenging the Transactions themselves, including any and all claims or causes of action alleging or contending that any aspect of the Transactions violates any Existing Document (as defined in the Transaction Support Agreement) or other agreement, or that cooperation with, participation in, or entering into the Transactions violates any statute or other law, it being understood that the Consenting Parties are ratifying and approving all such Transactions to the maximum extent possible under applicable law. In addition, for the avoidance of doubt, the releases and discharges granted hereunder by each of the Consenting Parties are not limited to the loans, securities or other interests or positions that they hold as of the Effective Date or the Notes under the Indenture, but are granted by the Consenting Parties in all capacities and with respect to all loans, securities or other interests held or acquired at any time that relate to the Borrower, the Loan Parties or any of their respective Affiliates. Further, subject to the occurrence of, and effective from and after, the Effective Date, each Consenting Noteholder hereby covenants and agrees not to, directly or indirectly, bring, maintain, or encourage any cause of action or other claim or proceeding against any Company Released Party or any other Consenting Noteholder relating to or arising out of any Consenting Party Released Claim. Each Consenting Noteholder further stipulates and agrees with respect to all Claims, that subject to the occurrence of, and effective from and after, the Effective Date and the consummation of the Transactions, it hereby waives, to the fullest extent permitted by applicable law, any and all provisions, rights, and benefits conferred by any applicable U.S. federal or state law, any foreign law, or any principle of common law, that would otherwise limit a release or discharge of any unknown Claims pursuant to this Section 13(b).

(c) EXCEPT AS OTHERWISE PROVIDED HEREIN, EACH PARTY HEREBY EXPRESSLY AGREES THAT THE RELEASED CLAIMS SHALL INCLUDE, WITHOUT LIMITATION, SUCH RELEASED CLAIMS ARISING PRIOR TO THE EFFECTIVE DATE AS A DIRECT OR INDIRECT RESULT OF THE GROSS NEGLIGENCE AND/OR WILLFUL MISCONDUCT OF ANY COMPANY RELEASED PARTY OR OTHER RELEASED PARTY. EACH PARTY AGREES THAT THE COMPANY RELEASED PARTIES AND OTHER RELEASED PARTIES ARE EXPRESSLY INTENDED AS THIRD-PARTY BENEFICIARIES OF THIS SECTION 13.

(d) Each Consenting Noteholder and each of the Issuer and the Guarantors acknowledges that it is aware that it or its attorneys may hereafter discover claims or facts in addition to or different from those which they now know or believe to exist with respect to either the subject matter of this Supplemental Indenture and the Transactions or any party hereto, but hereto further acknowledges that it is the intention of each of the Issuer and the Guarantors and each Consenting Noteholder to hereby fully, finally, and forever settle and release all claims among them to the extent provided in this Supplemental Indenture, whether known or unknown, suspected or unsuspected, which now exist, may exist, or heretofore have existed.

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Notwithstanding the foregoing Sections 13(a), 13(b), 13(c) and 13(d), nothing in this Supplemental Indenture is intended to, and shall not, (i) release any party’s rights and obligations under this Supplemental Indenture or any of the Definitive Documents (as defined in the Transaction Support Agreement), (ii) bar any party from seeking to enforce or effectuate this Supplemental Indenture or any of the Definitive Documents (as defined in the Transaction Support Agreement) or (iii) release any payment obligation of the Issuer or any Guarantor (or their subsidiaries) under the Notes Documents (as defined in the Indenture).

14. AUTHORIZATION OF THE TRANSACTIONS. The Consenting Noteholders hereby expressly authorize, consent to, ratify and permit the Transactions and any transactions directly relating thereto or reasonably required to effect such Transactions in all respects. The Indenture is hereby supplemented to expressly authorize, consent to, ratify, and permit the Transactions.

[Signature page follows]

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed as of the date first above written.

[Signature Page to Second Supplemental Indenture – 2027 Notes]

[Signature Page to Second Supplemental Indenture – 2027 Notes]