Aprelis Acquisition Battle: Major Shareholders Secured.. Biogen Increases Success Potential with Support Agreement

On the afternoon of the 31st local time, Biogen Inc. (Nasdaq: BIIB) and its subsidiary, Aspen Purchaser Sub, Inc., entered into a tender-and-support agreement with major shareholders of Apellis Pharmaceuticals Inc. (Nasdaq: APLS) to back Biogen’s proposed tender offer and subsequent merger. Under the agreement, key investors—including Morningside Venture Investment and certain insiders—have agreed, subject to customary conditions, to tender all of their Apellis shares in Biogen’s offer, vote in favor of the merger proposal and against any competing acquisition bids. They will irrevocably grant Biogen their voting rights until the deal closes or the merger agreement terminates, and they are restricted from transferring shares or negotiating with third parties during that period.

Biogen has offered $41 in cash per Apellis share, plus up to $4 in performance-based earn-outs, valuing the transaction at approximately $5.6 billion (about ₩7.5 trillion). The company plans to use a short-form merger structure following the tender offer in order to expedite closing. The previous day, Biogen’s stock climbed over 1% after the U.S. Food and Drug Administration approved a high-dose formulation of Spinraza for spinal muscular atrophy, adding to a series of positive pipeline and business-expansion updates.

Headquartered in Cambridge, Massachusetts, Biogen is a multinational biotechnology company specializing in therapies for neurological disorders such as multiple sclerosis, Alzheimer’s disease and spinal muscular atrophy.

In recent years, global pharmaceutical and biotech firms have increasingly acquired companies with commercialized assets in immunology and rare diseases to diversify revenue streams. Biogen’s planned acquisition of Apellis is widely viewed as part of this broader external-growth strategy.