Day One Biopharmaceuticals, Inc. completed its acquisition of Mersana Therapeutics, Inc. on 2026-01-06, according to the Form 8-K Mersana Therapeutics, Inc. filed with the SEC on 2026-01-06. The filing states a price of $128.8 million. Mersana Therapeutics, Inc. filed the report because the deal made it part of Day One Biopharmaceuticals, Inc..
| Acquirer | Day One Biopharmaceuticals, Inc. |
|---|---|
| Acquired | Mersana Therapeutics, Inc. |
| Completed | 2026-01-06 |
| Price stated in the filing | $128.8 million |
| Reported by | Mersana Therapeutics, Inc. (MRSN), the company acquired |
| Filing | Form 8-K, filed 2026-01-06 |
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What the filing says
Following the consummation of the Offer, pursuant to the terms and conditions of the Merger Agreement, in accordance with Section 251(h) of the General Corporation Law of the State of Delaware (the "DGCL") and without a meeting or a vote of the Company's stockholders, on January 6, 2026, Purchaser was merged with and into the Company (the "Merger"), with the Company surviving the Merger as a direct wholly-owned subsidiary of Parent.
The price, in the filing's words
The aggregate cash paid by Parent and Merger Sub in the Offer and the Merger on January 6, 2026 was approximately $128.8 million, which was funded by Parent from its available cash on hand.
More from the filing
As previously disclosed in its Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission (the "SEC") on November 13, 2025, Mersana Therapeutics, Inc., a Delaware corporation (the "Company"), entered into an Agreement and Plan of Merger (the "Merger Agreement"), dated as of November 12, 2025, by and among the Company, Day One Biopharmaceuticals, Inc., a Delaware corporation ("Parent"), and Emerald Merger Sub, Inc., a Delaware corporation and a direct wholly-owned subsidiary of Parent ("Purchaser").
Pursuant to the Merger Agreement, on December 5, 2025, Purchaser commenced a tender offer (the "Offer") to acquire all of the issued and outstanding shares (the "Shares") of common stock, par value $0.0001 per share, of the Company (the "Common Stock"), for (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding(the "Upfront Cash Consideration"), plus (ii) one non-tradeable contingent value right per Share (each, a "CVR" and collectively, the "CVRs"), which represents the right to receive certain contingent milestone payments of up to an a
The Offer and related withdrawal rights expired as scheduled at one minute after 11:59 p.m., Eastern Time, on January 5, 2026 (such date and time, the "Expiration Time"), and were not extended.
Quoted from Mersana Therapeutics, Inc.'s Form 8-K; also reported in Form 8-K of 2026-01-06.
This is the only completed acquisition Day One Biopharmaceuticals, Inc. reported under Item 2.01 in the last twelve months, as far as the filings of the companies it bought show.
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Get the free SnapshotWhere this comes from
A public company must file a current report on Form 8-K with the SEC within four business days of completing a significant acquisition or disposition of assets, under Item 2.01 of the report. The acquired company sometimes files one too, when the deal makes it a subsidiary of the buyer.
Every fact on this page is taken from one of those filings and linked to it: which company acquired which, the date the filing gives for completion, and the price when the filing states one in dollars, shown next to the sentence that states it. A filing states what was bought and on what terms; it rarely states why, and neither does this page.