Key Notes
- Silence Therapeutics closed at $19.58 on October 19, gaining 125.58% after Merck’s cash acquisition announcement.
- The buyer is offering $20 per ADS, valuing Silence’s equity at approximately $1.3 billion and its enterprise at $1.1 billion.
- The deal targets a first-quarter 2027 close, while shareholder, court and regulatory approvals remain required.
Silence Therapeutics plc (NASDAQ: SLN) surged 125.58% to close at $19.58 on October 19 after Germany’s Merck KGaA agreed to acquire the biotechnology company for approximately $1.3 billion in cash equity value.
The $20 offer for each American depositary share, or ADS, would more than double the value of holders’ shares compared with Friday’s closing price. Merck KGaA (XETRA: MRK) announced the agreement as a move to strengthen its specialty and rare-disease pipeline.
The transaction is expected to close in the first quarter of 2027, subject to approvals and other conditions. The stock-market jump reflects investors pricing in a proposed cash acquisition, while ownership of Silence has yet to change.
A $20 Cash Offer Drives the SLN Rally
Silence ended Friday at $8.68 before Monday’s rise, according to trading data. Its closing price on Monday remained 42 cents below the offer, leaving approximately 2.1% potential upside to the agreed consideration before any costs or taxes, if the transaction completes on those terms.
That remaining difference is a deal spread. It reflects factors including the time until payment and the possibility that an acquisition is delayed, changes or fails. It should not be confused with the much larger premium over the pre-announcement price.
Silence’s own announcement puts the offer premium at approximately 130% over Friday’s close and 82% over its 30-day volume-weighted average price of $10.99. Those benchmarks explain why the company’s stated premium differs from Monday’s 125.58% trading gain.
Each ADS represents three ordinary shares. The equivalent consideration for an ordinary share is $6.6667, making the $20 headline amount specific to the Nasdaq-traded depositary security.
Merck Is Buying an Investigational Rare-Disease Program
The central asset is Divesiran, an experimental small interfering RNA, or siRNA, therapy for polycythemia vera. The rare blood cancer involves excessive production of red blood cells and can carry cardiovascular and clotting risks.
Merck describes Divesiran as ready for Phase 3 development. It is designed to silence the TMPRSS6 gene, increasing the iron-regulating hormone hepcidin and limiting iron available for red blood cell production. The aim is to reduce patients’ need for therapeutic blood removal, known as phlebotomy.
The buyer reported an 88% responder rate against 19% for placebo in the Phase 2 SANRECO study. Those are company-reported clinical findings, not a cure rate or a regulatory approval. Larger studies and the subsequent regulatory process remain important to the program’s commercial prospects.
For Merck, the proposed acquisition provides a route into hematology and adds a specialized development asset. Its healthcare business operates as EMD Serono in the United States and Canada; the purchaser is the Darmstadt-based German group.
Equity Value and Enterprise Value Measure Different Things
The companies put equity value at approximately $1.3 billion and enterprise value at $1.1 billion. The former describes the value assigned to shareholders’ equity, while enterprise value adjusts for balance-sheet items such as cash and debt.
The two figures therefore describe different aspects of the same transaction. The lower enterprise value does not mean Nasdaq investors are being offered less than $20 per ADS under the agreement.
Merck says it plans to fund the acquisition with proceeds from new debt. That is the buyer’s financing plan, distinct from how Silence holders would receive the agreed cash consideration.
Shareholders, Courts and Regulators Still Have a Role
Silence’s SEC filing says the agreement was signed October 18. The acquisition is structured as a UK scheme of arrangement, requiring shareholder approval and sanction by the High Court of Justice of England and Wales, alongside relevant antitrust clearances.
The filing says completion is not subject to a financing condition. That removes one contractual condition without removing the other requirements or guaranteeing the timetable.
Securityholders representing approximately 14% of Silence’s voting power have entered support agreements. That backing is meaningful, but it does not itself satisfy all the shareholder approvals required to complete the scheme.
A Pipeline Acquisition Changes the Investment Case
The transaction follows other efforts by large drugmakers to acquire specialized research programs. As we previously reported, Novartis AG (NYSE: NVS) agreed earlier this year to acquire Excellergy to strengthen its immunology pipeline.
For Silence holders, the near-term focus now shifts from a standalone assessment of future drug sales toward the agreed cash price and the path to completion. For Merck, the longer-term test will be whether clinical development, approvals and eventual commercialization justify the acquisition and subsequent investment.
Monday’s gain is substantial, but it does not establish that the outcome was predictable before the announcement. The next concrete milestones are the scheme documents, shareholder votes and required clearances ahead of the targeted early-2027 closing.
