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Polymer Capital Management’s Biogen BIIB Stock Holding History

Polymer Capital Management’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
Q2 		$303K Buy
+1,404
New +$269K 0.04% 508
2026
Q1 		– Sell
-5,022
Closed -$884K – 832
2025
Q4 		$884K Buy
5,022
+2,348
+88% +$384K 0.09% 324
2025
Q3 		$375K Sell
2,674
-1,086
-29% -$147K 0.04% 505
2025
Q2 		$472K Sell
3,760
-120
-3% -$15K 0.06% 268
2025
Q1 		$531K Buy
+3,880
New +$555K 0.14% 152

Other funds holding BIIB

Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
Primecap Management
Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return
Wellington Management Group
Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return
Norges Bank
Norges Bank Oslo, Norway $1T AUM
Morgan Stanley
Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return

Polymer Capital Management's BIIB Position: Q2 2026 in Review

Polymer Capital Management opened a new position in Biogen (BIIB) in Q2 2026: 1,404 shares worth $303K. The stake represents 0.04% of the portfolio and ranks #508 among its holdings. This is a return to the name: Polymer Capital Management previously reported a position in BIIB as recently as Q4 2025.

Polymer Capital Management first reported a position in BIIB in Q1 2025 and has held it in 5 quarters since. The position peaked at $884K in Q4 2025. 1,043 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

  • Polymer Capital Management held 1,404 shares of Biogen worth $303K as of Q2 2026.
  • Biogen was a new Polymer Capital Management position in Q2 2026.
  • Biogen made up 0.04% of Polymer Capital Management's portfolio in Q2 2026, its #508 holding.
  • Polymer Capital Management first reported a position in Biogen in Q1 2025 and has held it in 5 quarters since.
  • Polymer Capital Management's Biogen position peaked at $884K in Q4 2025.
  • 1,043 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on Polymer Capital Management's 13F filing for Q2 2026, filed 14 Aug 2026.