BIOGEN INC · CUSIP 09062X103 · CIK 1306923
As of 2026-06-30, Palo Alto Investors LP reported 140.28K BIIB (shares), valued at $30.31M, or 4.19% of its reported non-derivative portfolio. Filed 2026-08-19.
Verify history & sources →Shares decreased 0.31%; reported value increased 17.48%, and weight changed +0.24 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds.
Left: % · Right: Shares · Independently scaled axes
Exact data and methodology
Axes scale independently; a crossing does not mean equal values. Weight uses each quarter's total reported non-derivative value. Same CUSIP; missing quarters are gaps, not zero. Revised history may include later disclosures.
| Quarter | Weight | Quantity | Source |
|---|---|---|---|
| Q2 2026 | 4.19% | 140,279 | SEC filing ↗Filed Aug 19, 2026Amended |
| Q1 2026 | 3.95% | 140,719 | SEC filing ↗Filed May 15, 2026 |
| Q4 2025 | 4.50% | 183,571 | SEC filing ↗Filed Feb 17, 2026 |
| Q3 2025 | 4.81% | 185,661 | SEC filing ↗Filed Nov 14, 2025 |
| Q2 2025 | 5.50% | 205,759 | SEC filing ↗Filed Aug 14, 2025 |
| Q1 2025 | 5.34% | 204,923 | SEC filing ↗Filed May 15, 2025 |
| Q4 2024 | 4.51% | 190,148 | SEC filing ↗Filed Feb 14, 2025 |
| Q3 2024 | 5.76% | 228,916 | SEC filing ↗Filed Nov 14, 2024 |
| Q2 2024 | 7.76% | 289,050 | SEC filing ↗Filed Aug 14, 2024 |
| Q1 2024 | 7.05% | 289,958 | SEC filing ↗Filed May 15, 2024 |
| Q4 2023 | 8.87% | 380,417 | SEC filing ↗Filed Feb 15, 2024Amended |
History & evidence by quarter
| Quarter | Weight | Quantity | Value | Change explained | Source |
|---|---|---|---|---|---|
| Q4 2023 | 8.87% | 380,417 | $98.44M | The prior quarter is outside the free window. Sign in for the comparison. | SEC filing ↗ Filed Feb 15, 2024 |
| Q1 2024 | 7.05% | 289,958 | $62.52M | Shares decreased 23.78%; reported value decreased 36.49%, and weight changed -1.82 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2024 |
| Q2 2024 | 7.76% | 289,050 | $67.01M | Shares decreased 0.31%; reported value increased 7.17%, and weight changed +0.71 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 14, 2024 |
| Q3 2024 | 5.76% | 228,916 | $44.37M | Shares decreased 20.80%; reported value decreased 33.78%, and weight changed -2.00 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Nov 14, 2024 |
| Q4 2024 | 4.51% | 190,148 | $29.08M | Shares decreased 16.94%; reported value decreased 34.47%, and weight changed -1.25 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 14, 2025 |
| Q1 2025 | 5.34% | 204,923 | $28.04M | Shares increased 7.77%; reported value decreased 3.56%, and weight changed +0.83 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2025 |
| Q2 2025 | 5.50% | 205,759 | $25.84M | Shares increased 0.41%; reported value decreased 7.85%, and weight changed +0.16 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 14, 2025 |
| Q3 2025 | 4.81% | 185,661 | $26.01M | Shares decreased 9.77%; reported value increased 0.64%, and weight changed -0.69 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Nov 14, 2025 |
| Q4 2025 | 4.50% | 183,571 | $32.31M | Shares decreased 1.13%; reported value increased 24.22%, and weight changed -0.31 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 17, 2026 |
| Q1 2026 | 3.95% | 140,719 | $25.80M | Shares decreased 23.34%; reported value decreased 20.15%, and weight changed -0.55 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2026 |
| Q2 2026 | 4.19% | 140,279 | $30.31M | Shares decreased 0.31%; reported value increased 17.48%, and weight changed +0.24 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 19, 2026 |
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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.