American Century Companies’s Spero Therapeutics SPRO Stock Holding History

Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake
Trade Value Portfolio Weight Portfolio Position
2026
Q2
$81.4K Buy
+36,811
New +$96.3K ﹤0.01% 2845
2025
Q4
Sell
-40,219
Closed -$75.6K 2878
2025
Q3
$75.6K Buy
+40,219
New +$88.4K ﹤0.01% 2757

Other funds holding SPRO

American Century Companies's SPRO Position: Q2 2026 in Review

American Century Companies opened a new position in Spero Therapeutics (SPRO) in Q2 2026: 36,811 shares worth $81.4K. The stake represents ﹤0.01% of the portfolio and ranks #2845 among its holdings. This is a return to the name: American Century Companies previously reported a position in SPRO as recently as Q3 2025.

American Century Companies first reported a position in SPRO in Q3 2025 and has held it in 2 quarters since. 34 funds tracked by Wall St. Rank hold SPRO as of Q2 2026.

  • American Century Companies held 36,811 shares of Spero Therapeutics worth $81.4K as of Q2 2026.
  • Spero Therapeutics was a new American Century Companies position in Q2 2026.
  • Spero Therapeutics made up ﹤0.01% of American Century Companies's portfolio in Q2 2026, its #2845 holding.
  • American Century Companies first reported a position in Spero Therapeutics in Q3 2025 and has held it in 2 quarters since.
  • 34 funds tracked by Wall St. Rank held Spero Therapeutics as of Q2 2026.

Based on American Century Companies's 13F filing for Q2 2026, filed 12 Aug 2026.