Biogen Closes $5.6B Apellis Acquisition, APLS Delisted
NEW YORK, May 23 —
Apellis Pharmaceuticals ceased trading as an independent public company on May 14, 2026, when Biogen filed an 8-K disclosing the acquisition's close and a concurrent Nasdaq delisting notice. Shareholders received $41.00 per share in cash plus a contingent value right of up to $4.00 per share, on a total deal valued at roughly $5.6 billion. Nine days later, the company and its pipeline exist only inside a larger organization, with the CVR's outcome still open.
- $5.6 billion total deal value; $41.00 cash per share plus a CVR of up to $4.00 per share
- 82.4% of APLS shares tendered into Biogen's offer ahead of the May 14 close
- Trailing twelve-month revenue of $1.11 billion, growing 60.9% year-over-year; gross margin of 64.3%
A Clean Path to the Close
The Hart-Scott-Rodino antitrust waiting period expired before the merger date, per filings, clearing the regulatory track without apparent complication. The shareholder math was similarly unambiguous: with 82.4% of shares already tendered by the time Biogen submitted the final paperwork, the outcome was decided before anyone rang a closing bell. Apellis's May 14 8-K checked every required disclosure box in rapid succession — completion of acquisition, changes in control of the registrant, and notice of Nasdaq delisting, all landing simultaneously. The delisting was not procedural afterthought; it was the capstone, formalizing that APLS no longer exists as a public security.
What Biogen Bought
The business Biogen absorbed was generating $1.11 billion in trailing twelve-month revenue, growing at 60.9% year-over-year, with a 64.3% gross margin. Those are not distressed-seller numbers. Most acquisitions at this scale involve some gap between peak expectations and financial reality; Apellis's trajectory gave Biogen limited room to argue price. The company was unprofitable on a GAAP basis — most recent quarterly EPS of -$0.33 — but it was beating expectations by $0.14 per share against a consensus estimate of -$0.47. Rapid revenue growth with narrowing losses in a specialty pharmaceutical niche is not a seller's weakness. It is a seller's leverage.
The CVR Question
The $41.00 cash component is settled. The contingent value right, worth up to $4.00 per share, is not. CVRs are a standard mechanism when acquirer and target disagree about the value of future milestones — typically tied to regulatory approvals or commercial performance benchmarks — allowing the acquirer to cap initial outlay while preserving the option to pay fair value if the pipeline delivers. Biogen's subsequent quarterly filings will be the primary source for the specific trigger conditions attached to the Apellis CVR. Former shareholders holding CVRs have a real but contingent claim, its timing and probability entirely dependent on how the underlying programs perform inside a new owner.
Exit Day at Apellis
The paperwork cascade from a merger close arrives fast. On May 14, 2026, Form 4 filings were submitted for more than a dozen Apellis officers, including CFO Timothy Eugene Sullivan, Chief Scientific Officer Pascal Deschatelets, Chief Research and Development Officer Leslie Meltzer, Chief Technical Officer Nur Nicholson, and Chief Business and Strategy Officer Mark Jeffrey Delong. The transactions were classified as non-market dispositions, consistent with equity award conversion at the merger price rather than open-market selling. Separately, the 8-K's Items 5.02 and 5.03 documented director departures and bylaw amendments — the governance machinery of a company folding itself into an acquirer.
What to Watch
The remaining live variable is the CVR. Biogen's next quarterly filings and any integration disclosures will carry the milestone definitions that determine whether the extra $4.00 per share materializes. Whether those triggers are tied to regulatory submissions, approval decisions, or commercial thresholds will shape how former shareholders model the residual claim. Apellis's complement-focused pipeline — the asset that justified a $5.6 billion price — now competes for resources and attention inside a larger neurological franchise. How Biogen prioritizes those programs will become visible in its R&D spending disclosures over the next several quarters.
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Basis Report does not hold positions in securities discussed. This is not investment advice.
Frequently Asked Questions
What did Biogen pay for Apellis Pharmaceuticals?
Biogen paid $41.00 per share in cash plus a contingent value right of up to $4.00 per share, on a total deal valued at approximately $5.6 billion. The transaction closed on May 14, 2026.
What is the Apellis CVR and will it pay out?
The contingent value right entitles former Apellis shareholders to up to $4.00 per share if defined future milestones are met. The specific trigger conditions will appear in subsequent Biogen filings; payment is not guaranteed.
Is APLS stock still trading on Nasdaq?
No. Apellis's May 14, 2026 8-K included a Nasdaq delisting notice filed concurrent with the merger close. APLS shares are no longer publicly traded.
How did Apellis shareholders vote on the merger?
Acceptance was decisive: 82.4% of APLS shares were tendered into Biogen's offer ahead of the May 14 close, well above any typical threshold required to complete the transaction.
What were Apellis's financials before the Biogen deal?
Apellis reported trailing twelve-month revenue of $1.11 billion growing at 60.9% year-over-year, with a 64.3% gross margin. Its most recent quarterly GAAP EPS of -$0.33 beat the consensus estimate of -$0.47 by $0.14 per share.