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BIIBBIIB
Showing 8 of 31 quarters

Position history for PRIMECAP MANAGEMENT CO/CA/PRIMECAP MANAGEMENT CO/CA/'s holdings in BIOGEN INC

Yes. Primecap holds 15,154,606 shares of BIIB (Biogen), worth $3.3B, as of its Q2 2026 13F filing. It increased the position by 396,999 shares (+2.7%) from Q1 2026. Primecap has held BIIB in every 13F on record since Q4 2018, 31 quarterly filings. BIIB is 1.9% of Primecap's reported 13F portfolio.

Current Value

$3.3B

Current Shares

15.2M

Total Value Change

+$111.8M

Total Shares Change

-1.2M

Quarter-by-Quarter History
QuarterActionSharesChangeValueWeightPriceConviction
2026-Q2
Latest
Increased
15.2M
+2.7%
$3.3B1.9%$216.06
52
2026-Q1
Decreased
14.8M
0.0%
$2.7B2.1%$183.33
0
2025-Q4
Decreased
14.8M
-1.3%
$2.6B2.0%$175.99
0
2025-Q3
Decreased
15M
-5.4%
$2.1B1.6%$140.08
0
2025-Q2
Decreased
15.8M
-0.9%
$2B1.6%$125.59
0
2025-Q1
Decreased
15.9M
-0.6%
$2.2B1.8%$136.84
0
2024-Q4
Decreased
16M
-1.6%
$2.5B1.9%$152.92
0
2024-Q3
Decreased
16.3M
-0.1%
$3.2B2.3%$193.84
0

Other major holders of BIIB: FMR LLC, BlackRock Finance, Inc., BlackRock, Inc., VANGUARD GROUP INC

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