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Lee Ainslie’s Boston Scientific BSX Stock Holding History

Lee Ainslie’s Portfolio BSX Stock Details BSX Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$253M Buy
5,937,553
+1,742,464
+42% +$94.6M 2.24% 19
2026
Q1 		$263M Buy
4,195,089
+1,250,835
+42% +$100M 3.04% 9
2025
Q4 		$281M Buy
+2,944,254
New +$289M 3.01% 10
2024
Q2 		– Sell
-5,748
Closed -$394K – 295
2024
Q1 		$394K Sell
5,748
-3,083
-35% -$198K 0.01% 278
2023
Q4 		$511K Buy
+8,831
New +$471K 0.01% 187
2021
Q4 		– Sell
-62,528
Closed -$2.71M – 361
2021
Q3 		$2.71M Sell
62,528
-32,668
-34% -$1.45M 0.03% 146
2021
Q2 		$4.07M Buy
95,196
+62,070
+187% +$2.61M 0.04% 108
2021
Q1 		$1.28M Sell
33,126
-36,915
-53% -$1.4M 0.01% 206
2020
Q4 		$2.52M Buy
70,041
+5,745
+9% +$207K 0.04% 109
2020
Q3 		$2.46M Buy
+64,296
New +$2.48M 0.05% 114
2019
Q1 		– Sell
-77,730
Closed -$2.75M – 281
2018
Q4 		$2.75M Buy
+77,730
New +$2.82M 0.04% 230
2018
Q2 		– Sell
-71,740
Closed -$1.96M – 250
2018
Q1 		$1.96M Buy
+71,740
New +$1.95M 0.03% 194

Other funds holding BSX

BlackRock
BlackRock New York $6.73T AUM 46.02% 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
Primecap Management
Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
Massachusetts Financial Services
Massachusetts Financial Services Boston, Massachusetts $315B AUM 27.84% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
D.E. Shaw & Co
D.E. Shaw & Co New York $210B AUM 57.28% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return

Lee Ainslie's BSX Position: Q2 2026 in Review

Lee Ainslie increased its Boston Scientific (BSX) stake by 42% in Q2 2026, buying an estimated $94.6M and bringing the position to 5,937,553 shares worth $253M. The position accounts for 2.24% of the portfolio, ranked #19.

Lee Ainslie first reported a position in BSX in Q1 2018 and has held it in 12 quarters since. The position peaked at $281M in Q4 2025. 1,468 funds tracked by Wall St. Rank hold BSX as of Q2 2026.

  • Lee Ainslie held 5,937,553 shares of Boston Scientific worth $253M as of Q2 2026.
  • Lee Ainslie bought 1,742,464 Boston Scientific shares in Q2 2026, an estimated $94.6M.
  • Boston Scientific made up 2.24% of Lee Ainslie's portfolio in Q2 2026, its #19 holding.
  • Lee Ainslie first reported a position in Boston Scientific in Q1 2018 and has held it in 12 quarters since.
  • Lee Ainslie's Boston Scientific position peaked at $281M in Q4 2025.
  • 1,468 funds tracked by Wall St. Rank held Boston Scientific as of Q2 2026.

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