BIIB Biogen Inc.
Biogen Inc. (BIIB) Institutional Ownership
What the institutions did with BIIB last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.
Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.
Sign in or subscribeLargest holders
| Manager | Shares | % of reported |
|---|---|---|
| FMR LLC | 18.2M | 12.8% |
| BlackRock, Inc. | 16.0M | 11.2% |
| PRIMECAP MANAGEMENT CO/CA/ | 15.2M | 10.7% |
| VANGUARD CAPITAL MANAGEMENT LLC | 9.7M | 6.8% |
| STATE STREET CORP | 7.3M | 5.2% |
| VANGUARD PORTFOLIO MANAGEMENT LLC | 6.6M | 4.6% |
| GEODE CAPITAL MANAGEMENT, LLC | 4.4M | 3.1% |
| WELLINGTON MANAGEMENT GROUP LLP | 3.1M | 2.2% |
| NORGES BANK | 2.6M | 1.8% |
| MORGAN STANLEY | 2.4M | 1.7% |
| AQR CAPITAL MANAGEMENT LLC | 1.9M | 1.4% |
| JPMORGAN CHASE & CO | 1.8M | 1.3% |
| Invesco Ltd. | 1.8M | 1.3% |
| Amundi | 1.5M | 1.1% |
| Legal & General Group Plc | 1.5M | 1.0% |
| NORTHERN TRUST CORP | 1.4M | 1.0% |
| Boston Partners | 1.3M | 0.9% |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 1.3M | 0.9% |
| GOLDMAN SACHS GROUP INC | 1.2M | 0.9% |
| DIMENSIONAL FUND ADVISORS LP | 1.1M | 0.8% |
| Pacer Advisors, Inc. | 1.1M | 0.8% |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 1.1M | 0.8% |
| BANK OF AMERICA CORP /DE/ | 1.1M | 0.8% |
| UBS Group AG | 1.0M | 0.7% |
| Alyeska Investment Group, L.P. | 932.4K | 0.7% |
Largest changes
| Manager | Action | Previous | Current | Change |
|---|---|---|---|---|
| FMR LLC | Increased | 12.8M | 18.2M | +5.4M |
| T. Rowe Price Investment Management, Inc. | Reduced | 1.2M | 113.9K | -1.0M |
| VAN ECK ASSOCIATES CORP | Reduced | 1.1M | 98.1K | -981.8K |
| Amundi | Increased | 790.8K | 1.5M | +726.0K |
| Point72 Asset Management, L.P. | Reduced | 809.6K | 88.1K | -721.5K |
| UBS Group AG | Increased | 523.5K | 1.0M | +506.7K |
| Pacer Advisors, Inc. | Increased | 660.4K | 1.1M | +462.6K |
| Boston Partners | Reduced | 1.7M | 1.3M | -436.6K |
| PRIMECAP MANAGEMENT CO/CA/ | Increased | 14.8M | 15.2M | +397.0K |
| Balyasny Asset Management L.P. | Reduced | 650.0K | 265.1K | -385.0K |
| BARCLAYS PLC | Reduced | 551.5K | 247.2K | -304.3K |
| CITADEL ADVISORS LLC | Increased | 138.1K | 418.4K | +280.3K |
| PERCEPTIVE ADVISORS LLC | New | 0 | 276.2K | +276.2K |
| MORGAN STANLEY | Increased | 2.2M | 2.4M | +240.3K |
| CITIGROUP INC | Increased | 500.5K | 734.5K | +234.0K |
| Sofinnova Investments, Inc. | Sold Out | 229.5K | 0 | -229.5K |
| MARSHALL WACE, LLP | Reduced | 229.9K | 12.6K | -217.3K |
| Qube Research & Technologies Ltd | Sold Out | 212.9K | 0 | -212.9K |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | Reduced | 333.5K | 129.6K | -203.9K |
| Logos Global Management LP | Sold Out | 200.0K | 0 | -200.0K |
| JPMORGAN CHASE & CO | Reduced | 2.0M | 1.8M | -192.9K |
| VOYA INVESTMENT MANAGEMENT LLC | Increased | 54.6K | 246.8K | +192.2K |
| GOLDMAN SACHS GROUP INC | Increased | 1.1M | 1.2M | +179.3K |
| ROYAL BANK OF CANADA | Increased | 531.4K | 708.6K | +177.2K |
| STATE STREET CORP | Increased | 7.2M | 7.3M | +176.4K |
13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.