William Blair & Company
RGEN icon

William Blair & Company’s Repligen RGEN Stock Holding History

William Blair & Company’s Portfolio RGEN Stock Details RGEN Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2025
Q4 		– Sell
-1,992
Closed -$266K – 1929
2025
Q3 		$266K Sell
1,992
-754
-27% -$91.6K ﹤0.01% 1348
2025
Q2 		$342K Buy
2,746
+676
+33% +$86K ﹤0.01% 1215
2025
Q1 		$263K Sell
2,070
-10
-0.5% -$1.54K ﹤0.01% 1303
2024
Q4 		$299K Sell
2,080
-5
-0.2% -$717 ﹤0.01% 1286
2024
Q3 		$310K Sell
2,085
-683
-25% -$97.9K ﹤0.01% 1269
2024
Q2 		$349K Sell
2,768
-22,567
-89% -$3.54M ﹤0.01% 1215
2024
Q1 		$4.66M Sell
25,335
-2,024
-7% -$385K 0.01% 492
2023
Q4 		$4.92M Sell
27,359
-1,696
-6% -$264K 0.02% 468
2023
Q3 		$4.62M Sell
29,055
-15,413
-35% -$2.52M 0.02% 455
2023
Q2 		$6.29M Buy
44,468
+1,205
+3% +$193K 0.02% 399
2023
Q1 		$7.28M Sell
43,263
-231
-0.5% -$41.2K 0.03% 358
2022
Q4 		$7.36M Buy
43,494
+4,103
+10% +$744K 0.03% 348
2022
Q3 		$7.37M Buy
39,391
+4,306
+12% +$908K 0.03% 335
2022
Q2 		$5.7M Buy
35,085
+32,250
+1,138% +$5.1M 0.03% 398
2022
Q1 		$533K Sell
2,835
-478
-14% -$90.8K ﹤0.01% 1131
2021
Q4 		$877K Buy
3,313
+225
+7% +$60.6K ﹤0.01% 1007
2021
Q3 		$892K Sell
3,088
-30
-1% -$7.7K ﹤0.01% 972
2021
Q2 		$622K Sell
3,118
-1,005
-24% -$195K ﹤0.01% 1078
2021
Q1 		$802K Sell
4,123
-2,705
-40% -$555K ﹤0.01% 971
2020
Q4 		$1.31M Sell
6,828
-78
-1% -$14.2K ﹤0.01% 772
2020
Q3 		$1.02M Buy
6,906
+757
+12% +$108K ﹤0.01% 752
2020
Q2 		$760K Buy
6,149
+80
+1% +$9.41K ﹤0.01% 808
2020
Q1 		$586K Sell
6,069
-16,100
-73% -$1.55M ﹤0.01% 823
2019
Q4 		$2.05M Sell
22,169
-1,658
-7% -$139K 0.01% 600
2019
Q3 		$1.83M Sell
23,827
-4,840
-17% -$423K 0.01% 594
2019
Q2 		$2.46M Sell
28,667
-5,428
-16% -$370K 0.01% 524
2019
Q1 		$2.01M Sell
34,095
-345
-1% -$19.8K 0.01% 565
2018
Q4 		$1.82M Sell
34,440
-2,441
-7% -$143K 0.01% 541
2018
Q3 		$2.04M Sell
36,881
-1,067
-3% -$55K 0.01% 552
2018
Q2 		$1.78M Sell
37,948
-53
-0.1% -$2.18K 0.01% 584
2018
Q1 		$1.38M Sell
38,001
-21,352
-36% -$751K 0.01% 628
2017
Q4 		$2.15M Sell
59,353
-34,888
-37% -$1.26M 0.01% 548
2017
Q3 		$3.61M Buy
94,241
+41,405
+78% +$1.74M 0.03% 411
2017
Q2 		$2.19M Buy
52,836
+3,579
+7% +$136K 0.02% 549
2017
Q1 		$1.73M Buy
49,257
+1,193
+2% +$37.8K 0.01% 576
2016
Q4 		$1.48M Buy
48,064
+410
+0.9% +$12.7K 0.01% 565
2016
Q3 		$1.44M Sell
47,654
-5,270
-10% -$159K 0.01% 563
2016
Q2 		$1.45M Buy
52,924
+11,630
+28% +$297K 0.01% 532
2016
Q1 		$1.11M Buy
+41,294
New +$1.01M 0.01% 597
2015
Q4 		– Sell
-57,894
Closed -$1.61M – 1267
2015
Q3 		$1.61M Sell
57,894
-168,836
-74% -$6.1M 0.01% 595
2015
Q2 		$9.36M Sell
226,730
-140,663
-38% -$5.15M 0.01% 905
2015
Q1 		$11.2M Buy
367,393
+74,125
+25% +$1.92M 0.02% 822
2014
Q4 		$5.81M Buy
293,268
+143,268
+96% +$3.2M 0.01% 1012
2014
Q3 		$2.99M Buy
+150,000
New +$3.16M 0.01% 1140

Other funds holding RGEN

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
Vanguard Group
Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return
T. Rowe Price Associates
T. Rowe Price Associates Baltimore, Maryland $865B AUM 30.76% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
UCFA
United Capital Financial Advisors Irving, Texas $16.3B AUM 16.34% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
Citadel Advisors
Citadel Advisors Miami, Florida $618B AUM 30.34% 1-Year Est. Return
Bank of New York Mellon
Bank of New York Mellon New York $544B AUM 28.31% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.02T AUM 30.18% 1-Year Est. Return
Massachusetts Financial Services
Massachusetts Financial Services Boston, Massachusetts $298B AUM 21.96% 1-Year Est. Return

William Blair & Company's RGEN Position: Q4 2025 in Review

William Blair & Company sold out of Repligen (RGEN) in Q4 2025, closing a stake of 1,992 shares — an estimated $266K sold.

William Blair & Company first reported a position in RGEN in Q3 2014 and held it in 44 quarters. The position peaked at $11.2M in Q1 2015. 473 funds tracked by Wall St. Rank hold RGEN as of Q4 2025.

  • William Blair & Company reported no remaining Repligen position as of Q4 2025 after selling out during the quarter.
  • William Blair & Company sold 1,992 Repligen shares in Q4 2025, an estimated $266K.
  • William Blair & Company first reported a position in Repligen in Q3 2014 and held it in 44 quarters.
  • William Blair & Company's Repligen position peaked at $11.2M in Q1 2015.
  • 473 funds tracked by Wall St. Rank held Repligen as of Q4 2025.

Based on William Blair & Company's 13F filing for Q4 2025, filed 17 Feb 2026.