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Stocks / United States / BIIB / Holders

Biogen Inc. 13F holders

Of the 44 funds followed here, 9 reported a position in Biogen Inc. in a 13F for the quarter ended 30 June 2026. The largest: FMR LLC, 18.2 million shares worth $3.94 billion, 0.2% of its reported book.

FundSharesValueOf its bookChange on the quarterStatusQuarter endedFiling
FMR LLC18,217,239$3.94 billion0.2%+5,409,698added30 June 202613F
Geode Capital Management4,449,295$957.9 million0.1%+106,693added30 June 202613F
Norges Bank2,580,033$557.4 million0.1%held30 June 202613F
Alyeska932,374$201.4 million0.5%+127,324added30 June 202613F
Citadel Advisors867,556$187.4 million0.0%+336,863added30 June 202613F
Point72 Asset Management88,749$19.2 million0.0%-725,568trimmed30 June 202613F
Renaissance Technologies77,744$16.8 million0.0%-125,652trimmed30 June 202613F
Millennium Management49,500$10.7 million0.0%-232,264trimmed30 June 202613F
Two Sigma Investments7,105$1.5 million0.0%-2,339trimmed30 June 202613F

Value is what the fund reported. Change is shares against the fund's previous 13F; a fund with one filing read shows no change. 13Fs cover long US positions of managers above $100 million and are filed up to 45 days after the quarter.

Schedule 13D and 13G filed on the name, last twelve months

FiledScheduleWhoHoldingOf the classEvent dateRule or purposeFiling
6 August 202613G/AFmr Llc and 3 others18.3 million12.4%30 June 2026passive, institutional (13d-1(b))EDGAR
5 June 202613G/AFmr Llc and 3 others16.7 million11.3%29 May 2026passive, institutional (13d-1(b))EDGAR
6 May 202613G/AFmr Llc and 3 others12.8 million8.7%31 March 2026passive, institutional (13d-1(b))EDGAR
29 April 202613GVanguard Capital Management and 1 other11.0 million7.5%31 March 2026passive, institutional (13d-1(b))EDGAR
26 March 202613G/AThe Vanguard Group and 1 other00.0%13 March 2026passive, institutional (13d-1(b))EDGAR
5 February 202613GFmr Llc and 3 others9.4 million6.4%31 December 2025passive, institutional (13d-1(b))EDGAR
13 November 202513G/APrimecap Management Co/Ca/ and 1 other15.0 million10.2%30 September 2025passive, institutional (13d-1(b))EDGAR
10 November 202513GState Street Corporation and 1 other7.3 million5.0%30 September 2025passive, institutional (13d-1(b))EDGAR

A Schedule 13D is filed by anyone who crosses 5% of a class with intent to influence; a 13G by a passive holder. Amendments (/A) report a change, including an exit to zero. Holding and percentage are as the filer stated them on the cover page; the purpose is the filer's own words, cut short.

Fails to deliver

Settlement dateShares failedPriceFile
28 August 2026991$221.50SEC
25 August 20263,091$218.12SEC
24 August 202693$216.78SEC
21 August 2026145$214.35SEC
7 August 2026135$206.28SEC
3 August 20262,347$202.95SEC
17 July 20268$208.92SEC
16 July 202663$197.24SEC

Shares that failed to deliver at settlement, per day, from the SEC's half-month files, which arrive about two weeks after the period. Largest in the window: 3,091 on 25 August 2026. A fail is an operational fact about settlement, not a position.

Source

Each fund's 13F-HR on EDGAR, linked per row; positions matched to BIIB by CUSIP from the SEC's own fails-to-deliver files; Schedule 13D and 13G from the company's own filing index, each read to confirm the company is the issuer named.

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