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BIIB position history

The shares of Biogen (BIIB) that Palo Alto Investors LP reported in each quarter’s 13F.

Equity, COM

Shares held by quarter

New Add Reduce Exit

  1. 2021 Q3: 361,600 shares, $102M, 6.2% of portfolio
  2. 2021 Q4: 385,000 shares, $92M, 5.9% of portfolio, Add +6.5%
  3. 2022 Q1: 360,981 shares, $76M, 5.9% of portfolio, Reduce −6.2%
  4. 2022 Q2: 360,981 shares, $74M, 6.4% of portfolio
  5. 2022 Q3: 360,981 shares, $96M, 7.6% of portfolio
  6. 2022 Q4: 380,082 shares, $105M, 9.0% of portfolio, Add +5.3%
  7. 2023 Q1: 381,282 shares, $106M, 8.8% of portfolio, Add +0.3%
  8. 2023 Q2: 381,282 shares, $109M, 8.8% of portfolio
  9. 2023 Q3: 381,282 shares, $98M, 9.3% of portfolio
  10. 2023 Q4: 760,834 shares, $197M, 17.8% of portfolio, Add +99.5%
  11. 2024 Q1: 289,958 shares, $63M, 7.1% of portfolio, Reduce −61.9%
  12. 2024 Q2: 289,050 shares, $67M, 7.8% of portfolio, Reduce −0.3%
  13. 2024 Q3: 228,916 shares, $44M, 5.8% of portfolio, Reduce −20.8%
  14. 2024 Q4: 190,148 shares, $29M, 4.5% of portfolio, Reduce −16.9%
  15. 2025 Q1: 204,923 shares, $28M, 5.3% of portfolio, Add +7.8%
  16. 2025 Q2: 205,759 shares, $26M, 5.5% of portfolio, Add +0.4%
  17. 2025 Q3: 185,661 shares, $26M, 4.8% of portfolio, Reduce −9.8%
  18. 2025 Q4: 183,571 shares, $32M, 4.5% of portfolio, Reduce −1.1%
  19. 2026 Q1: 140,719 shares, $26M, 3.9% of portfolio, Reduce −23.3%
  20. 2026 Q2: 140,279 shares, $30M, 4.2% of portfolio, Reduce −0.3%
Holdings date Value % of holdings Shares Filing date All 13F holders