Silence Therapeutics plc (SLN) stock intrinsic value fair value estimate & owner earnings analysis

Silence Therapeutics is a clinical-stage biotechnology company (headquartered in the United Kingdom, with US-listed ADSs) developing short interfering RNA (siRNA) medicines, including divesiran for polycythemia vera, zerlasiran for high lipoprotein(a), and partnered programs with AstraZeneca and Hansoh Pharmaceutical. It has no approved product. Revenue comes only from collaboration payments and was about $0.6 million in 2025, versus $43.3 million in 2024 and $31.6 million in 2023, as earlier upfront payments were recognized and not replaced. What the business earns for its owners: operating cash flow was negative $62.3 million in 2025 and negative $67.6 million in 2024. After deducting stock-based compensation ($8.1 million in 2025) and minimal capital spending, and stripping out working-capital timing, owner earnings were roughly negative $69 million in 2025 (about negative $0.49 per share), and between negative $0.41 and negative $0.68 per share in each of 2022-2024. There is no year of positive owner earnings to anchor a valuation on, and the trend is not improving: the most recent year was worse than 2024 per share. How we valued it: we only credit value that is secured or is the output of a repeatable process the company has already run. The company holds signed collaborations with substantial contingent payments (for example, up to about $1.3 billion in development, regulatory and commercial milestones from Hansoh, and up to $140 million of development milestones plus up to $250 million of commercial milestones per AstraZeneca target). But those payments depend on clinical, regulatory and sales outcomes that have not happened, and the company has never had a marketed product or a run of profitable years. Under our approach, that potential is not counted. The bear, base and bull cases therefore each come out at $0 per share. This does not mean shares must trade at zero; it means that nothing in the filings yet lets us name and evidence a stream of owner earnings to discount. The company's cash is also not added to the value. Earnings are measured after cash interest, so the cash needed to fund the losses is treated as consumed by the business, and cash is not counted on top. The bear case: continued cash burn of roughly $60-70 million a year with cash and short-term investments of $85.1 million at year-end 2025 (the company says this funds operations into 2028), followed by further share issuance at dilutive prices, as it did in 2024 ($120 million private placement and $27.7 million of at-the-market sales). Shareholders then own a smaller slice of a company with no earnings. The base case has the same outcome, since no earnings are evidenced. The bull case would need a partnered drug to reach approval and sales, a step not yet secured, so it is not counted. What would make this wrong: a partner-funded milestone (for example from AstraZeneca or Hansoh) or a positive late-stage readout on divesiran or zerlasiran would create real value. Milestones already received (such as $10 million from AstraZeneca and $2 million from Hansoh in 2024) show partners do pay, but they are lumpy, have not covered costs, and did not produce positive owner earnings in any year we measured. If such events occur and translate into recurring positive cash flow, the analysis should be revisited. We only have four years of comparable filing data, as earlier filings were made on a different form. No margin-of-safety price can be set today, because we cannot identify positive earning power to protect.