William Blair Investment Management
PEN icon

William Blair Investment Management’s Penumbra PEN Stock Holding History

William Blair Investment Management’s Portfolio PEN Stock Details PEN Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		– Sell
-345,974
Closed -$108M – 445
2025
Q4 		$108M Buy
+345,974
New +$95.6M 0.3% 93
2025
Q1 		– Sell
-883,098
Closed -$210M – 448
2024
Q4 		$210M Sell
883,098
-98,211
-10% -$22.3M 0.51% 54
2024
Q3 		$191M Buy
981,309
+156,330
+19% +$29.5M 0.47% 62
2024
Q2 		$148M Sell
824,979
-8,724
-1% -$1.74M 0.39% 82
2024
Q1 		$186M Buy
833,703
+90,444
+12% +$22.4M 0.48% 63
2023
Q4 		$187M Buy
743,259
+86,295
+13% +$19.1M 0.54% 55
2023
Q3 		$159M Sell
656,964
-13,322
-2% -$3.7M 0.53% 60
2023
Q2 		$231M Sell
670,286
-270,446
-29% -$83M 0.74% 30
2023
Q1 		$262M Sell
940,732
-248,238
-21% -$63.4M 0.91% 20
2022
Q4 		$264M Buy
1,188,970
+140,457
+13% +$27.5M 1.01% 18
2022
Q3 		$199M Buy
1,048,513
+75,838
+8% +$12.2M 0.79% 35
2022
Q2 		$121M Buy
972,675
+113,992
+13% +$18.1M 0.45% 78
2022
Q1 		$191M Sell
858,683
-242,871
-22% -$54M 0.57% 60
2021
Q4 		$316M Buy
1,101,554
+419,632
+62% +$111M 0.86% 24
2021
Q3 		$182M Sell
681,922
-8,778
-1% -$2.36M 0.51% 64
2021
Q2 		$189M Sell
690,700
-175,853
-20% -$48M 0.59% 65
2021
Q1 		$234M Sell
866,553
-469,710
-35% -$121M 0.76% 39
2020
Q4 		$234M Buy
1,336,263
+108,878
+9% +$23.9M 0.78% 34
2020
Q3 		$239M Sell
1,227,385
-44,428
-3% -$9.35M 0.93% 26
2020
Q2 		$227M Buy
1,271,813
+5,580
+0.4% +$968K 0.93% 24
2020
Q1 		$204M Buy
1,266,233
+48,046
+4% +$8.09M 0.99% 21
2019
Q4 		$200M Buy
1,218,187
+45,395
+4% +$7.22M 0.8% 31
2019
Q3 		$158M Buy
1,172,792
+214,195
+22% +$33.1M 0.67% 46
2019
Q2 		$153M Buy
958,597
+271,784
+40% +$39.3M 0.64% 53
2019
Q1 		$101M Sell
686,813
-4,089
-0.6% -$584K 0.42% 74
2018
Q4 		$84.4M Buy
+690,902
New +$92.5M 0.42% 75

Other funds holding PEN

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
HI
HBK Investments Dallas, Texas $9.85B AUM 55.6% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
Millennium Management
Millennium Management New York $240B AUM 35.51% 1-Year Est. Return
Baillie Gifford & Co
Baillie Gifford & Co Edinburgh, United Kingdom $97.9B AUM 20.73% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
Balyasny Asset Management
Balyasny Asset Management Chicago, Illinois $77.1B AUM 42.89% 1-Year Est. Return
Goldman Sachs
Goldman Sachs New York $871B AUM 31.28% 1-Year Est. Return

William Blair Investment Management's PEN Position: Q1 2026 in Review

William Blair Investment Management sold out of Penumbra (PEN) in Q1 2026, closing a stake of 345,974 shares — an estimated $108M sold.

William Blair Investment Management first reported a position in PEN in Q4 2018 and held it in 26 quarters. The position peaked at $316M in Q4 2021. 482 funds tracked by Wall St. Rank hold PEN as of Q1 2026.

  • William Blair Investment Management reported no remaining Penumbra position as of Q1 2026 after selling out during the quarter.
  • William Blair Investment Management sold 345,974 Penumbra shares in Q1 2026, an estimated $108M.
  • William Blair Investment Management first reported a position in Penumbra in Q4 2018 and held it in 26 quarters.
  • William Blair Investment Management's Penumbra position peaked at $316M in Q4 2021.
  • 482 funds tracked by Wall St. Rank held Penumbra as of Q1 2026.

Based on William Blair Investment Management's 13F filing for Q1 2026, filed 8 May 2026.