Adicet Bio (ACET) updates 10-K to confirm effective 2025 controls

Rhea-AI Filing Summary

Adicet Bio, Inc. filed an amended annual report to update its disclosure on controls and procedures for the year ended December 31, 2025. The company explains that its original Form 10-K omitted required statements about the effectiveness and design of its disclosure controls and procedures.

Management, including the CEO and CFO, evaluated these disclosure controls and concluded they were effective as of December 31, 2025 and are designed to provide reasonable assurance that required information is properly recorded and reported. They also concluded that internal control over financial reporting was effective at the reasonable assurance level as of the same date, based on the COSO framework, without an auditor attestation because Adicet Bio is a non-accelerated filer.

The amendment does not change the company’s financial statements or other disclosures, and it states that the filing is not an admission that the original report contained any material misstatement or omission. As of June 30, 2025, non-affiliate common stock had an aggregate market value of about $50.5 million, and as of May 19, 2026, there were 9,348,236 common shares outstanding.

Key Figures

Non-affiliate market value: $50.5 million Share price: $0.61 per share Shares outstanding: 9,348,236 shares +2 more

5 metrics

Non-affiliate market value $50.5 million Aggregate market value as of June 30, 2025

Share price $0.61 per share Closing price on June 30, 2025 on The Nasdaq Global Market

Shares outstanding 9,348,236 shares Common stock outstanding as of May 19, 2026

Filer status Non-accelerated filer Status used to explain no auditor attestation requirement

Controls evaluation date December 31, 2025 Effective date for disclosure and internal control assessments

Key Terms

disclosure controls and procedures, internal control over financial reporting, reasonable assurance, non-accelerated filer, +1 more

5 terms

disclosure controls and procedures regulatory

"Our management, with the participation of our Chief Executive Officer... evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2025."

Policies, routines and internal checks a public company uses to identify, collect and verify information that must appear in its financial reports and public filings, and to make sure that material news is disclosed accurately and on time. Investors care because effective controls increase confidence that the company’s reported numbers and disclosures are reliable and reduce the risk of surprises, much like a building’s inspection and alarm system helps occupants trust the structure’s safety.

internal control over financial reporting regulatory

"Our management is responsible for establishing and maintaining adequate internal control over our financial reporting..."

Internal control over financial reporting is a company’s system of procedures and checks designed to make sure its financial statements are accurate and complete, like a set of guardrails and verification steps that catch mistakes or fraud before numbers are published. Investors care because strong controls make reported results more trustworthy, lower the risk of surprise restatements or regulatory problems, and give greater confidence when valuing the company or comparing it to peers.

reasonable assurance financial

"Our disclosure controls and procedures are designed to provide reasonable assurance of achieving their objectives."

non-accelerated filer regulatory

"As we are a non-accelerated filer, management’s report is not subject to attestation by our registered public accounting firm."

A non-accelerated filer is a publicly traded company whose market value and regulatory status place it in the smaller reporting category, so it faces longer deadlines and fewer near-term compliance requirements for filing financial reports with regulators. For investors, that matters because smaller companies often provide financial updates on a slower timetable and are subject to lighter external audit rules, which can affect how quickly new information reaches the market.

Inline XBRL technical

"101.INS* | | Inline XBRL Instance Document 101.SCH* | | Inline XBRL Taxonomy Extension Schema Document"

Inline XBRL is a file format for financial filings that embeds machine-readable data tags directly inside the human-readable report, so the same document can be read by people and parsed by software. For investors it makes extracting, comparing and verifying financial numbers faster and more reliable—like a grocery list where each item also has a barcode—reducing manual errors and speeding up analysis.

How to Read a 10-K Annual Report →

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

Amendment No. 1

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission File No. 001-38359

Adicet Bio, Inc.

(Exact name of registrant as specified in its charter)

Delaware		81-3305277
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification No.)

131 Dartmouth Street, 3rd Floor

Boston, MA 02116

(650) 503-9095

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, par value $0.0001 per share	ACET	The Nasdaq Capital Market

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ☐ Yes ☒ No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. ☐ Yes ☒ No

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, 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	☐			Accelerated filer	☐
Non-accelerated filer	☒			Smaller reporting company	☒
				Emerging growth company	☐

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). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act.): ☐ Yes ☒ No

As of June 30, 2025, the aggregate market value of the registrant’s voting and non-voting common stock held by non-affiliates was approximately $50.5 million based on a closing price of $0.61 per share as quoted by The Nasdaq Global Market on June 30, 2025. In determining the market value of non-affiliate common stock, shares of the registrant’s common stock beneficially owned by officers, directors and affiliates have been excluded. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

As of May 19, 2026, there were 9,348,236 shares of common stock, $0.0001 par value per share, outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Part III of this Annual Report on Form 10-K incorporates by reference certain information from the registrant’s definitive Proxy Statement for its 2026 annual meeting of shareholders, scheduled to be held on June 17, 2026, which the registrant has filed pursuant to Regulation 14A with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year end of December 31, 2025. Except with respect to information specifically incorporated by reference in this Form 10-K, the Proxy Statement is not deemed to be filed as part of this Form 10-K.

EXPLANATORY NOTE

This amended report on Form 10-K/A (the “Amendment”) amends the Annual Report on Form 10-K of Adicet Bio, Inc. (the “Company”) for the year ended December 31, 2025, initially filed with the Securities and Exchange Commission (the “SEC”) on March 12, 2026 (the “Original Filing”), for the purpose of updating the disclosure in Item 9A “Controls and Procedures.” The Original Filing inadvertently omitted (a) a statement disclosing the conclusions of the Company’s principal executive and principal financial officers regarding the effectiveness of the Company’s disclosure controls and procedures as of December 31, 2025 and (b) a statement that the disclosure controls and procedures are designed to provide reasonable assurance of achieving their objectives and the conclusions of the principal executive officer and principal financial officer that the controls and procedures are, in fact, effective at the reasonable assurance level. This Amendment corrects such omission and amends and replaces Item 9A “Controls and Procedures” in its entirety.

Except as described above, no other changes are being made to the Original Filing, and this Amendment consists only of the facing page, this explanatory note, Item 9A “Controls and Procedures” and the signature page to the Amendment. Further, except as expressly stated, this Amendment does not reflect events occurring after the filing of the Original Filing or modify or update in any way any of the other items or disclosures contained in the Original Filing, including, without limitation, the consolidated financial statements and the related footnotes. Accordingly, this Amendment should be read in conjunction with the Original Filing and the Registrant’s other filings with the SEC subsequent to the filing of the Original Filing. The filing of this Amendment is not an admission that the Original Filing, when filed, included any untrue statement of a material fact or omitted to state a material fact necessary to make a statement not misleading.

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PART II

Item 9A. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer (CEO) and our Chief Financial Officer (CFO) (our principal executive officer and principal financial officer, respectively), evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2025. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC's rules and forms.

Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company's management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. There are inherent limitations to the effectiveness of any system of disclosure controls and procedures. These limitations include the possibility of human error, the circumvention or overriding of the controls and procedures and reasonable resource constraints. In addition, because we have designed our system of controls based on certain assumptions, which we believe are reasonable, about the likelihood of future events, our system of controls may not achieve its desired purpose under all possible future conditions. Our disclosure controls and procedures are designed to provide reasonable assurance of achieving their objectives. Based on that evaluation, our management, with the participation of our Chief Executive Officer and Chief Financial Officer, have concluded that our disclosure controls and procedures were effective as of December 31, 2025. Accordingly, management believes that the financial statements included in this Annual Report on Form 10-K present fairly in all material respects our financial position, results of operations and cash flows for the period presented.

Management’s Annual Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over our financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act). Our internal control over financial reporting is designed to provide reasonable assurances regarding the reliability of financial reporting and the preparation of our consolidated financial statements in accordance with U.S. GAAP, and includes those policies and procedures that:

•Pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the Company;

•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 authorization of management and directors of the Company; and

•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.

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, assessed our internal control over financial reporting as of December 31, 2025. Management based its assessment on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission and concluded that our internal control over financial reporting was effective at the reasonable assurance level as of December 31, 2025.

This Annual Report on Form 10-K does not include an attestation report from our registered public accounting firm regarding internal control over financial reporting. As we are a non-accelerated filer, management’s report is not subject to attestation by our registered public accounting firm.

3

We cannot assure you that material weaknesses or significant deficiencies will not occur in the future or that we will be able to remediate such weaknesses or deficiencies in a timely manner, which could impair our ability to accurately and timely report our financial position, results of operations or cash flows. For additional information, see the related risks in the section entitled "Risk Factors" of this Annual Report on Form 10-K.

Changes in Internal Control over Financial Reporting

Other than the remediation plan described in our Annual Report on Form 10-K filed with the SEC on March 6, 2025, no change in our internal control over our financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the year ended December 31, 2025 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Internal Controls

An effective internal control system, no matter how well designed, has inherent limitations, including the possibility of human error 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 the consolidated financial statements.

4

PART IV

Item 15. Exhibits, Financial Statement Schedules.

The following documents are filed as exhibits to this Amendment:

EXHIBIT INDEX

Exhibit Number		Description of Exhibit
31.1*		Certification of Principal Executive Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2*		Certification of Principal Financial Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
101.INS*		Inline XBRL Instance Document
101.SCH*		Inline XBRL Taxonomy Extension Schema Document
101.CAL*		Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF*		Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB*		Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE*		Inline XBRL Taxonomy Extension Presentation Linkbase Document
104*		Cover Page Interactive Data File

* Filed herewith.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	Adicet Bio, Inc.
Date: May 20, 2026	By:	/s/ Chen Schor
		Chen Schor President, Chief Executive Officer and Director (Principal Executive Officer)

FAQ

What does Adicet Bio (ACET) change in its 10-K/A amendment?

Adicet Bio amends its annual report to add missing statements on disclosure controls and procedures. Management now explicitly concludes these controls were effective as of December 31, 2025 and designed to provide reasonable assurance that required information is properly captured and reported.

Were Adicet Bio’s disclosure controls effective as of December 31, 2025?

Yes. Management, including the CEO and CFO, evaluated Adicet Bio’s disclosure controls and procedures and concluded they were effective as of December 31, 2025. These controls are designed to provide reasonable assurance that required SEC reporting information is recorded, processed, summarized, and communicated in a timely way.

How does Adicet Bio assess its internal control over financial reporting?

Adicet Bio’s management assessed internal control over financial reporting as of December 31, 2025 using the COSO Internal Control—Integrated Framework. They concluded controls were effective at the reasonable assurance level for reliable financial reporting and U.S. GAAP compliance, noting inherent limitations such as possible human error or control overrides.

Does Adicet Bio’s amended report include an auditor attestation on internal controls?

No. The amended report states there is no attestation report from the registered public accounting firm on internal control over financial reporting. Adicet Bio is a non-accelerated filer, so only management’s assessment is included, consistent with applicable SEC rules for this filer category.

What is Adicet Bio’s market value and share count mentioned in the 10-K/A?

As of June 30, 2025, Adicet Bio’s non-affiliate common stock had an aggregate market value of approximately $50.5 million, based on a $0.61 per share closing price. As of May 19, 2026, the report states there were 9,348,236 shares of common stock outstanding.

Does the Adicet Bio 10-K/A amendment change previously reported financial statements?

No. The amendment states it does not modify or update the consolidated financial statements or other disclosures from the original annual report. It is limited to correcting the omission in Item 9A, replacing the controls and procedures section and adding related officer certifications and Inline XBRL exhibits.