Biogen Inc. (BIIB)

FairStock Score: 39/100 — MIXED

Key Financials

AI Analysis

AI-generated, general educational analysis — not personal investment advice.

I look at Biogen as a specialist in neurological and rare-disease therapies, with approved products for multiple sclerosis, spinal muscular atrophy, ALS, and Friedreich's ataxia. That niche can carry patents and specialist know-how, but the numbers show a business under pressure rather than a wide-moat compounder. In fiscal 2025, the year ended 2025-12-31, revenue was $9.9B, net income $1.3B, and diluted EPS $8.79. In fiscal 2024, the year ended 2024-12-31, revenue was $9.7B, net income $1.6B, and diluted EPS $11.18. In fiscal 2023, the year ended 2023-12-31, revenue was $9.8B, net income $1.2B, and diluted EPS $7.97. Revenue is essentially flat over three years, while profits have swung wildly and are down sharply from 2024. FairStock classifies it as a SLOW GROWER — Shrinking, with profits falling about 20.2% a year over five years and revenue down 6.0%. The balance sheet is not alarming: debt-to-equity is 0.44, free cash flow is $2.5B, and FCF yield is 7.4%. But returns are weak: ROE 4.58% and ROCE 5.21%, and the Piotroski F-Score is only 4/9. Altman Z-Score is 2.71. At the 2026-10-13 close of $228.90, FairStock calculates a P/E of 40.73, P/B of 1.79, and EV/EBITDA of 19.10. The Graham Number is $127.03, leaving a negative margin of safety of -80.19%. For a shrinking, low-return business, that is not Graham's idea of a bargain. I would need evidence that new therapies can restart durable profit growth before paying such a premium.

In plain English: Biogen makes medicines for brain and nerve diseases such as multiple sclerosis, spinal muscular atrophy and ALS. Its profits have been falling and the returns it earns on its money are low, so the business looks weak right now. At $228.90 on 2026-10-13, the stock looks expensive compared with its earnings and asset value.

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Data as of 2026-10-13 close · note generated 2026-10-15 · model deepseek-flash

Sources (SEC EDGAR): fiscal Q1 2026 10-Q (period ended 2026-03-31) · fiscal Q3 2025 10-Q (period ended 2025-09-30) · fiscal Q2 2025 10-Q (period ended 2025-06-30) · fiscal Q1 2025 10-Q (period ended 2025-03-31) · FY2025 10-K (period ended 2025-12-31) · FY2024 10-K (period ended 2024-12-31) · FY2023 10-K (period ended 2023-12-31)

Fundamentals from company filings and market-data providers; prices are end-of-day, not real-time. AI-generated analysis is general and educational — not personal investment advice. Scoring methodology · Score test · Disclaimer