Cullinan Therapeutics, Inc.

In addition to the other information set forth in this Quarterly Report on Form 10-Q, you should carefully consider the factors discussed in Part I, “Item 1A. Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2025 (the “2025 10-K"), which could materially affect our business, financial condition or future results. The risk factors disclosure in our 2025 10-K is qualified by the information that is described in this Quarterly Report on Form 10-Q. The risks described in our 2025 10-K are not our only risks. Additional risks and uncertainties not presently known to us or that we currently believe to be immaterial also may materially adversely affect our business, financial condition or future results. There have been no material changes to our risk factors as previously disclosed in the 2025 10-K except as follows:

We will no longer qualify as a “smaller reporting company” after December 31, 2026, and, as a result, following the expiration of the SEC's transition period, we may become subject to additional disclosure and compliance requirements.

We are currently a “smaller reporting company” (“SRC”) under the Securities and Exchange Commission (“SEC”) rules. However, because the market value of our common stock held by non-affiliates exceeded $700 million as of June 30, 2026, we will no longer qualify as an SRC after December 31, 2026. Under the SEC’s transition period applicable to companies that cease to qualify as SRCs under the revenue test, we will remain eligible to use certain accommodations applicable to non-accelerated filers for filings due during 2027. Accordingly, we will not be required to include an auditor attestation on the effectiveness of internal control over financial reporting in our Annual Report on Form 10-K for the year ended December 31, 2026.

After the applicable transition period ends, we will be required to reassess our filer status under the SEC’s rules. Based on the rules currently in effect we expect that we would become an accelerated filer or large accelerated filer as of December 31, 2027.

If we become an accelerated filer or large accelerated filer, in the future we will be subject to certain disclosure and compliance requirements that apply to other public companies but that did not previously apply to us due to our status as an SRC. These requirements include, but are not limited to:

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the requirement that we obtain stockholder approval of any golden parachute payments not previously approved.

We expect that the loss of SRC status and compliance with the additional requirements of being a large accelerated filer, if and when applicable, will increase our legal, accounting and financial compliance costs and costs associated with investor relations activities, and cause management and other personnel to divert attention from operational and other business matters to devote substantial time to public company reporting requirements. In addition, if we are not able to comply with changing requirements in a timely manner, the market price of our stock could decline and we could be subject to sanctions or investigations by the stock exchange on which our common stock is listed, the SEC or other regulatory authorities, which would require additional financial and management resources.