William Blair & Company
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William Blair & Company’s Monolithic Power Systems MPWR Stock Holding History

William Blair & Company’s Portfolio MPWR Stock Details MPWR Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2014
Q4 		– Sell
-2,000
Closed -$88K – 2129
2014
Q3 		$88K Buy
+2,000
New +$88K ﹤0.01% 2028

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Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Vanguard Portfolio Management
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Invesco
Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return
T. Rowe Price Associates
T. Rowe Price Associates Baltimore, Maryland $999B AUM 46.22% 1-Year Est. Return
Franklin Resources
Franklin Resources San Mateo, California $462B AUM 39.16% 1-Year Est. Return
Goldman Sachs
Goldman Sachs New York $1.15T AUM 47.82% 1-Year Est. Return

William Blair & Company's MPWR Position: Q2 2026 in Review

William Blair & Company reduced its Monolithic Power Systems (MPWR) stake by 0.98% in Q2 2026, selling an estimated $447K and leaving 30,259 shares worth $41.8M. The position accounts for 0.11% of the portfolio, ranked #164.

William Blair & Company first reported a position in MPWR in Q2 2013 and has held it in 49 quarters since. 1,243 funds tracked by Wall St. Rank hold MPWR as of Q2 2026.

  • William Blair & Company held 30,259 shares of Monolithic Power Systems worth $41.8M as of Q2 2026.
  • William Blair & Company sold 298 Monolithic Power Systems shares in Q2 2026, an estimated $447K.
  • Monolithic Power Systems made up 0.11% of William Blair & Company's portfolio in Q2 2026, its #164 holding.
  • William Blair & Company first reported a position in Monolithic Power Systems in Q2 2013 and has held it in 49 quarters since.
  • 1,243 funds tracked by Wall St. Rank held Monolithic Power Systems as of Q2 2026.

Based on William Blair & Company's 13F filing for Q2 2026, filed 11 Aug 2026.