BIIB — Biogen Idec Inc COM

Ownership history in CAPITAL FUND MANAGEMENT S.A.  ·  139 quarters on record

AI Ownership Summary

CAPITAL FUND MANAGEMENT S.A. reported Biogen Idec Inc COM (BIIB) in 139 quarterly 13F filings from 2023 Q4 through 2025 Q4. Peak portfolio weight reached 0.16% in 2025 Q1. The latest visible filing shows BIIB at 0.03% of the fund.

This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings. Older history is available after unlock; the visible window still shows the most recent pattern.

What this BIIB ownership page tells you

This page is designed to answer the real investor question behind a 13F filing: how meaningful was CAPITAL FUND MANAGEMENT S.A.'s position in Biogen Idec Inc COM, and how did that conviction change over time? You can read the holding window, peak weight, latest reported size, disclosure timing, and quarter-by-quarter changes without piecing the story together from raw SEC rows.

Freshest filing
Latest Reported Filing
2025 Q4

BIIB was reported at 0.03% of portfolio in the most recent visible filing.

High-water mark
Peak Conviction
0.16% in 2025 Q1

Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.

Time in book
Holding Window
2023 Q4 to 2025 Q4

Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.

Decision context
Why It Matters
Position size beats headlines

Knowing that a fund owned a stock is useful. Knowing whether it was a 0.20% placeholder or a true high-conviction position is where the signal actually starts.

BIIB stock page CAPITAL FUND MANAGEMENT S.A. fund profile CAPITAL FUND MANAGEMENT S.A. full holdings
How CAPITAL FUND MANAGEMENT S.A. held BIIB — position size vs. price
% of Fund (quarterly)    BIIB price (quarter-end, indexed to 100)
📋 Quarterly Holdings History 25 quarters  ▾
Quarter Action Shares Change Chg % % of Fund Mkt Value Filed Price (Filed)
2025 Q4 ADDED 61,900 +14,400 +30.3% 0.03% $10.9M 2026-02-14 (Est.) $196.52
2025 Q4 REDUCED 47,500 -43,100 -47.6% 0.02% $8.4M 2026-02-14 (Est.) $196.52
2025 Q3 ADDED 90,600 +19,100 +26.7% 0.03% $12.7M 2025-11-13 $164.73
2025 Q3 ADDED 71,500 +23,773 +49.8% 0.03% $10.0M 2025-11-13 $164.73
2025 Q3 REDUCED 47,727 -60,473 -55.9% 0.02% $6.7M 2025-11-13 $164.73
2025 Q2 REDUCED 108,200 -9,494 -8.1% 0.04% $13.6M 2025-08-13 $135.19
2025 Q2 REDUCED 117,694 -57,806 -32.9% 0.04% $14.8M 2025-08-13 $135.19
2025 Q2 REDUCED 175,500 -234,400 -57.2% 0.06% $22.0M 2025-08-13 $135.19
2025 Q1 ADDED 409,900 +185,400 +82.6% 0.16% $56.1M 2025-05-14 $120.37
2025 Q1 ADDED 224,500 +11,485 +5.4% 0.09% $30.7M 2025-05-14 $120.37
2025 Q1 REDUCED 213,015 -27,328 -11.4% 0.08% $29.1M 2025-05-14 $120.37
2024 Q4 ADDED 240,343 +116,843 +94.6% 0.09% $36.8M 2025-02-13 $138.45
2024 Q4 ADDED 123,500 +36,800 +42.4% 0.05% $18.9M 2025-02-13 $138.45
2024 Q4 ADDED 86,700 +20,900 +31.8% 0.03% $13.3M 2025-02-13 $138.45
2024 Q3 REDUCED 65,800 -120,137 -64.6% 0.03% $12.8M 2024-11-13 $165.79
2024 Q3 ADDED 185,937 +144,337 +347.0% 0.10% $36.0M 2024-11-13 $165.79
2024 Q3 REDUCED 41,600 -51,624 -55.4% 0.02% $8.1M 2024-11-13 $165.79
2024 Q2 ADDED 93,224 +12,724 +15.8% 0.06% $21.6M 2024-08-13 $204.05
2024 Q2 REDUCED 80,500 -600 -0.7% 0.05% $18.7M 2024-08-13 $204.05
2024 Q2 REDUCED 81,100 -6,900 -7.8% 0.06% $18.8M 2024-08-13 $204.05
2024 Q1 ADDED 88,000 +57,300 +186.6% 0.05% $19.0M 2024-05-15 $235.32
2024 Q1 REDUCED 30,700 -116,730 -79.2% 0.02% $6.6M 2024-05-15 $235.32
2024 Q1 ADDED 147,430 +99,830 +209.7% 0.09% $31.8M 2024-05-15 $235.32
2023 Q4 REDUCED 47,600 -37,500 -44.1% 0.03% $12.3M 2024-02-14 $220.74
2023 Q4 ADDED 85,100 +62,900 +283.3% 0.06% $22.0M 2024-02-14 $220.74
114 older quarters hidden  —  Sign in free or upgrade to Premium to see full history

🏢 Other funds also holding BIIB

As of 2026 Q1 — sorted by position size

Artemis Investment Management LLP 3Y 7Y 1.11% FARMERS TRUST CO 3Y 7Y 0.97% Insight Wealth Strategies, LLC 3Y 7Y 0.6% STABLEFORD CAPITAL II LLC 3Y 0.47% First County Bank /CT/ 0.41% TOWER TRUST & INVESTMENT Co 0.35% Generali Investments, Management Co LLC 0.3% RDA Financial Network 3Y 0.14% NorthCrest Asset Manangement, LLC 3Y 0.14% GATEWAY INVESTMENT ADVISERS LLC 3Y 7Y 0.1%

FAQ About CAPITAL FUND MANAGEMENT S.A. and BIIB

These are the practical questions this page is built to answer before you even open the full history table.

How long has CAPITAL FUND MANAGEMENT S.A. reported owning BIIB?

CAPITAL FUND MANAGEMENT S.A. reported BIIB across 25 quarterly 13F filings, from 2023 Q4 through 2025 Q4.

What was the largest reported BIIB position in CAPITAL FUND MANAGEMENT S.A.'s portfolio?

The largest reported portfolio weight for BIIB was 0.16% in 2025 Q1.

What is the latest reported BIIB position on this page?

The most recent filing on this page is 2025 Q4, when CAPITAL FUND MANAGEMENT S.A. reported 61,900 shares, equal to 0.03% of portfolio, with an estimated market value of $10.9M.

What does the chart on this BIIB ownership page compare?

The chart compares CAPITAL FUND MANAGEMENT S.A.'s quarterly BIIB portfolio weight with the stock's indexed share price, so you can see whether the fund was building, trimming, or holding the position as price moved.

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