SIG Brokerage’s Biogen BIIB Stock Holding History

SIG Brokerage’s Portfolio BIIB Stock Details BIIB Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	–	Sell	-8,700	Closed	-$1.53M	–	797
2025 Q4	$1.53M	Buy	+8,700	New	+$1.42M	0.05%	278

Other funds holding BIIB

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return

Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return

Norges Bank Oslo, Norway $1T AUM

Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return

SIG Brokerage's BIIB Position: Q2 2026 in Review

SIG Brokerage increased its Biogen (BIIB) stake by 24% in Q2 2026, buying an estimated $253K and bringing the position to 6,824 shares worth $1.47M. The position accounts for 0.03% of the portfolio, ranked #394.

SIG Brokerage first reported a position in BIIB in Q4 2024 and has held it in 7 quarters since. The position peaked at $1.92M in Q4 2025. 1,043 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

SIG Brokerage held 6,824 shares of Biogen worth $1.47M as of Q2 2026.
SIG Brokerage bought 1,324 Biogen shares in Q2 2026, an estimated $253K.
Biogen made up 0.03% of SIG Brokerage's portfolio in Q2 2026, its #394 holding.
SIG Brokerage first reported a position in Biogen in Q4 2024 and has held it in 7 quarters since.
SIG Brokerage's Biogen position peaked at $1.92M in Q4 2025.
1,043 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on SIG Brokerage's 13F filing for Q2 2026, filed 14 Aug 2026.