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. No regulatory complications were disclosed. The shareholder tally was equally clean: 82.4% of shares were tendered before Biogen submitted the final paperwork, clearing any required threshold before the closing date arrived. Apellis's May 14 8-K combined three disclosure items in a single filing — completion of the acquisition, change in control of the registrant, and Nasdaq delisting notice. The delisting was not administrative afterthought. It was the final step: APLS no longer exists as a publicly traded 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 deals at this scale close after the seller's growth has already peaked. Apellis's trajectory gave Biogen little room to argue on 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. Revenue growing 60.9% with losses narrowing 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 bridge valuation gaps: Biogen caps its upfront payment and agrees to pay more if Apellis's pipeline hits defined milestones — typically regulatory approvals or commercial performance benchmarks. The structure lets an acquirer close without paying full price for uncertain outcomes. Biogen's subsequent quarterly filings will contain the specific trigger conditions attached to the Apellis CVR. Former shareholders holding CVRs retain a contingent claim. Whether it pays, and when, depends entirely on how those 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 standard governance filings of a company transferring control to an acquirer.
What to Watch
The remaining variable is the CVR. Biogen's next quarterly filings and any integration disclosures will name the milestone definitions that determine whether the extra $4.00 per share materializes. The trigger conditions — regulatory submissions, approval decisions, or commercial thresholds — will determine how former shareholders value 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 allocates R&D spending toward those programs will be visible in its disclosures over the next several quarters.
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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.