William Blair & Company
ALT icon

William Blair & Company’s Altimmune ALT Stock Holding History

William Blair & Company’s Portfolio ALT Stock Details ALT Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$86.9K Sell
28,223
-28,211
-50% -$120K ﹤0.01% 1614
2025
Q4 		$204K Buy
+56,434
New +$246K ﹤0.01% 1460

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VPM
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Marshall Wace
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Millennium Management
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Geode Capital Management
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Alyeska Investment Group
Alyeska Investment Group Chicago, Illinois $35.4B AUM 33.54% 1-Year Est. Return
Two Sigma Investments
Two Sigma Investments New York $124B AUM 33.93% 1-Year Est. Return
N
Nuveen Charlotte, North Carolina $369B AUM 31.66% 1-Year Est. Return

William Blair & Company's ALT Position: Q1 2026 in Review

William Blair & Company reduced its Altimmune (ALT) stake by 50% in Q1 2026, selling an estimated $120K and leaving 28,223 shares worth $86.9K. The position accounts for ﹤0.01% of the portfolio, ranked #1614.

William Blair & Company first reported a position in ALT in Q4 2025 and has held it in 2 quarters since. The position peaked at $204K in Q4 2025. 173 funds tracked by Wall St. Rank hold ALT as of Q1 2026.

  • William Blair & Company held 28,223 shares of Altimmune worth $86.9K as of Q1 2026.
  • William Blair & Company sold 28,211 Altimmune shares in Q1 2026, an estimated $120K.
  • Altimmune made up ﹤0.01% of William Blair & Company's portfolio in Q1 2026, its #1614 holding.
  • William Blair & Company first reported a position in Altimmune in Q4 2025 and has held it in 2 quarters since.
  • William Blair & Company's Altimmune position peaked at $204K in Q4 2025.
  • 173 funds tracked by Wall St. Rank held Altimmune as of Q1 2026.

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