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Illinois Municipal Retirement Fund’s Biogen BIIB Stock Holding History

Illinois Municipal Retirement Fund’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 		$21.5M Buy
99,303
+10,000
+11% +$1.91M 0.24% 84
2026
Q1 		$16.4M Buy
89,303
+7,905
+10% +$1.46M 0.21% 112
2025
Q4 		$14.3M Sell
81,398
-1,722
-2% -$281K 0.18% 139
2025
Q3 		$11.6M Sell
83,120
-23,801
-22% -$3.22M 0.15% 168
2025
Q2 		$13.4M Buy
106,921
+42,783
+67% +$5.33M 0.18% 135
2025
Q1 		$8.78M Buy
64,138
+1,957
+3% +$280K 0.13% 208
2024
Q4 		$9.51M Buy
62,181
+12,166
+24% +$2.05M 0.13% 190
2024
Q3 		$9.69M Buy
50,015
+8,038
+19% +$1.68M 0.14% 200
2024
Q2 		$9.73M Sell
41,977
-7,140
-15% -$1.55M 0.15% 182
2024
Q1 		$10.6M Hold
49,117
– – 0.16% 170
2023
Q4 		$12.7M Sell
49,117
-19,274
-28% -$4.73M 0.21% 121
2023
Q3 		$17.6M Buy
68,391
+8,291
+14% +$2.22M 0.33% 52
2023
Q2 		$17.1M Buy
60,100
+3,708
+7% +$1.1M 0.34% 61
2023
Q1 		$15.7M Sell
56,392
-7,916
-12% -$2.19M 0.33% 74
2022
Q4 		$17.8M Sell
64,308
-5,295
-8% -$1.5M 0.4% 53
2022
Q3 		$18.6M Buy
69,603
+5,881
+9% +$1.25M 0.46% 41
2022
Q2 		$13M Buy
63,722
+18,180
+40% +$3.72M 0.3% 89
2022
Q1 		$9.59M Buy
45,542
+2,255
+5% +$490K 0.28% 105
2021
Q4 		$10.4M Buy
43,287
+7,221
+20% +$1.86M 0.29% 105
2021
Q3 		$10.2M Buy
36,066
+5,210
+17% +$1.71M 0.38% 52
2021
Q2 		$10.7M Buy
30,856
+8,002
+35% +$2.42M 0.43% 39
2021
Q1 		$6.39M Buy
22,854
+525
+2% +$142K 0.28% 101
2020
Q4 		$5.47M Buy
22,329
+11,973
+116% +$3.09M 0.26% 116
2020
Q3 		$2.94M Buy
10,356
+4,766
+85% +$1.33M 0.39% 41
2020
Q2 		$1.5M Buy
+5,590
New +$1.68M 0.62% 45

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

Illinois Municipal Retirement Fund's BIIB Position: Q2 2026 in Review

Illinois Municipal Retirement Fund increased its Biogen (BIIB) stake by 11% in Q2 2026, buying an estimated $1.91M and bringing the position to 99,303 shares worth $21.5M. The position accounts for 0.24% of the portfolio, ranked #84.

Illinois Municipal Retirement Fund first reported a position in BIIB in Q2 2020 and has held it in 25 quarters since. 1,043 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

  • Illinois Municipal Retirement Fund held 99,303 shares of Biogen worth $21.5M as of Q2 2026.
  • Illinois Municipal Retirement Fund bought 10,000 Biogen shares in Q2 2026, an estimated $1.91M.
  • Biogen made up 0.24% of Illinois Municipal Retirement Fund's portfolio in Q2 2026, its #84 holding.
  • Illinois Municipal Retirement Fund first reported a position in Biogen in Q2 2020 and has held it in 25 quarters since.
  • 1,043 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on Illinois Municipal Retirement Fund's 13F filing for Q2 2026, filed 12 Aug 2026.