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TCW Group’s Biogen BIIB Stock Holding History

TCW Group’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 		$532K Buy
2,461
+123
+5% +$23.5K ﹤0.01% 479
2026
Q1 		$429K Buy
2,338
+112
+5% +$20.6K ﹤0.01% 509
2025
Q4 		$392K Buy
+2,226
New +$364K ﹤0.01% 517
2017
Q1 		– Sell
-21,850
Closed -$6.2M – 411
2016
Q4 		$6.2M Buy
21,850
+1,953
+10% +$579K 0.05% 177
2016
Q3 		$6.23M Sell
19,897
-1,400
-7% -$415K 0.05% 172
2016
Q2 		$5.15M Buy
21,297
+1,493
+8% +$393K 0.04% 186
2016
Q1 		$5.16M Sell
19,804
-200
-1% -$52.8K 0.04% 185
2015
Q4 		$6.13M Buy
20,004
+654
+3% +$188K 0.04% 176
2015
Q3 		$5.65M Sell
19,350
-650
-3% -$215K 0.04% 174
2015
Q2 		$8.08M Sell
20,000
-50,259
-72% -$20.2M 0.05% 185
2015
Q1 		$29.7M Buy
70,259
+2,009
+3% +$792K 0.14% 136
2014
Q4 		$23.2M Sell
68,250
-49,450
-42% -$16M 0.1% 156
2014
Q3 		$38.9M Sell
117,700
-2,450
-2% -$808K 0.16% 137
2014
Q2 		$37.9M Buy
120,150
+1,350
+1% +$406K 0.16% 138
2014
Q1 		$36.3M Sell
118,800
-800
-0.7% -$254K 0.15% 130
2013
Q4 		$33.4M Sell
119,600
-550
-0.5% -$142K 0.14% 129
2013
Q3 		$28.9M Buy
120,150
+1,032
+0.9% +$231K 0.13% 131
2013
Q2 		$25.6M Buy
+119,118
New +$25.5M 0.13% 145

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

TCW Group's BIIB Position: Q2 2026 in Review

TCW Group increased its Biogen (BIIB) stake by 5.3% in Q2 2026, buying an estimated $23.5K and bringing the position to 2,461 shares worth $532K. The position accounts for ﹤0.01% of the portfolio, ranked #479.

TCW Group first reported a position in BIIB in Q2 2013 and has held it in 18 quarters since. The position peaked at $38.9M in Q3 2014. 1,043 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

  • TCW Group held 2,461 shares of Biogen worth $532K as of Q2 2026.
  • TCW Group bought 123 Biogen shares in Q2 2026, an estimated $23.5K.
  • Biogen made up ﹤0.01% of TCW Group's portfolio in Q2 2026, its #479 holding.
  • TCW Group first reported a position in Biogen in Q2 2013 and has held it in 18 quarters since.
  • TCW Group's Biogen position peaked at $38.9M in Q3 2014.
  • 1,043 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on TCW Group's 13F filing for Q2 2026, filed 3 Aug 2026.