fsly-20251231

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

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.

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 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to § 240.10D-1(b). ☐

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant, based on the closing price of $7.06 for a share of the Registrant’s Class A Common Stock ("common stock") on June 30, 2025 (the last business day of the registrant's most recently completed second quarter), as reported by the New York Stock Exchange on such date, was approximately $1.0 billion.

Fastly, Inc. (the “Company,” “we,” “us” or “our”) is filing this Amendment No. 1 on Form 10-K/A (this “Amendment”) to amend its Annual Report on Form 10-K for the year ended December 31, 2025, originally filed with the Securities and Exchange Commission (“SEC”) on February 25, 2026 (the “Original Filing”). Capitalized terms not otherwise defined in this Amendment shall have the same meanings assigned to such terms in the Original Filing.

This Amendment is being filed to revise Part II, Item 9A “Controls and Procedures” by adding a sentence disclosing management's assessment of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2025, which was inadvertently omitted from the Original Filing due to a typographical error. In accordance with Rule 12b-15 of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), this Amendment amends and restates in its entirety Part II, Item 9A “Controls and Procedures”. In addition, as required by Rule 12b-15, new certifications by the Company’s principal executive officer and principal financial officer are filed as exhibits to this Amendment.

Except as described above, this Amendment does not amend, update or change any other items or disclosures contained in the Original Filing, and accordingly, this Amendment does not reflect or purport to reflect any information or events occurring after the Original Filing date or modify or update those disclosures affected by subsequent events. Accordingly, this Amendment should be read in conjunction with the Original Filing.

Our disclosure controls and procedures are designed to ensure that information we are required to disclose in reports that we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in SEC rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and our Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.

Our management, with the participation of our Chief Executive Officer and our Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act) as of December 31, 2025. Based on such evaluation, our Chief Executive Officer and our Chief Financial Officer have concluded that as of December 31, 2025, our disclosure controls and procedures were, in design and operation, effective at a reasonable assurance level.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting and for the assessment of the effectiveness of internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act. Our management conducted an assessment of the effectiveness of our internal control over financial reporting as of December 31, 2025 based on the criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on this assessment, our management concluded that our internal control over financial reporting was effective as of December 31, 2025. The effectiveness of our internal control over financial reporting as of December 31, 2025 has been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in its report which is included in Item 9A of this Annual Report on Form 10-K.

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that a reasonable possibility exists that a material misstatement of our annual or interim financial statements would not be prevented or detected on a timely basis.

As previously reported in Item 9A of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, management identified a material weakness in the fiscal year ended December 31, 2024. The previously reported material weakness related to deficiencies in the design and operating effectiveness of controls within the revenue process. These deficiencies related to certain business process controls primarily caused by a lack of sufficiently qualified personnel due to

turnover, information technology general controls, including the failure to receive a service auditor’s report for our billing system hosted by a third-party, and insufficient monitoring controls over such third-party service providers.

•Enhanced our controls over the ongoing monitoring of third-party service providers, including timely receipt of relevant service auditor reports to evidence design, implementation, and operating effectiveness of controls within the service organization’s framework of internal controls; and

•Enhanced the design and effectiveness of controls over the timely input of complete and accurate customer contract information that is used for the processing and recording of billing and revenue transactions in our systems.

The above mentioned measures have been implemented for a sufficient period of time and management has concluded, through testing, that the enhanced controls are operating effectively. Management concluded that the deficiencies leading to the material weakness were remediated as of December 31, 2025.

As described above, we implemented changes to our internal control over financial reporting to remediate the material weakness that was previously identified. There were no other changes during the quarter ended December 31, 2025 in our internal control over financial reporting that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

An effective internal control system, no matter how well designed, has inherent limitations, including the possibility of human error or overriding of controls, and therefore can provide only reasonable assurance with respect to reliable financial reporting. Because of its inherent limitations, our internal control over financial reporting may not prevent or detect all misstatements, including the possibility of human error, the circumvention or overriding of controls, or fraud. Effective internal controls can provide only reasonable assurance with respect to the preparation and fair presentation of financial statements.

We have audited the internal control over financial reporting of Fastly, Inc. and subsidiaries (the “Company”) as of December 31, 2025, based on criteria established in Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control—Integrated Framework (2013) issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements as of and for the year ended December 31, 2025, of the Company and our report dated February 25, 2026, expressed an unqualified opinion on those financial statements.

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management’s Annual Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Exhibit
Number

Exhibit Description

Form

File No.

Exhibit

Filing Date

Filed Herewith

31.1

Certification of the Chief Executive Officer pursuant to Exchange Act Rule 13a-14 as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

31.2

Certification of the Chief Financial Officer pursuant to Exchange Act Rule 13a-14 as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

101. INS

Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.

101.SCH

Inline XBRL Taxonomy Schema Linkbase Document.

101.CAL

Inline XBRL Taxonomy Calculation Linkbase Document.

101.DEF

Inline XBRL Taxonomy Definition Linkbase Document.

101.LAB

Inline XBRL Taxonomy Labels Linkbase Document.

101.PRE

Inline XBRL Taxonomy Presentation Linkbase Document.

104

Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101).

FASTLY, INC.

Date:

November 10, 2026

By:

/s/ Charles Compton

Charles Compton

Chief Executive Officer (Principal Executive Officer)

Date:

November 10, 2026

By:

/s/ Richard Wong

Richard Wong

Chief Financial Officer (Principal Financial Officer)


Delaware						27-5411834
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification Number)