Simplex Trading
SPRO icon

Simplex Trading’s Spero Therapeutics SPRO Stock Holding History

Simplex Trading’s Portfolio SPRO Stock Details SPRO Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$77.7K Buy
33,200
+14,800
+80% +$35.1K ﹤0.01% 5370
2025
Q4 		$42.9K Sell
18,400
-9,700
-35% -$22.5K ﹤0.01% 5802
2025
Q3 		$52K Sell
28,100
-140,700
-83% -$309K ﹤0.01% 6432
2025
Q2 		$489K Buy
168,800
+165,700
+5,345% +$238K ﹤0.01% 3530
2025
Q1 		$2K Buy
+3,100
New +$2.62K ﹤0.01% 8073
2023
Q3 		– Sell
-3,800
Closed -$5K – 9756
2023
Q2 		$5K Buy
+3,800
New +$6.5K ﹤0.01% 7959
2023
Q1 		– Sell
-26,900
Closed -$46K – 10064
2022
Q4 		$46K Buy
26,900
+24,000
+828% +$44.8K ﹤0.01% 5996
2022
Q3 		$5K Sell
2,900
-7,000
-71% -$6.96K ﹤0.01% 8819
2022
Q2 		$7K Buy
+9,900
New +$28.8K ﹤0.01% 8628
2021
Q4 		– Sell
-1,600
Closed -$26K – 11369
2021
Q3 		$26K Buy
1,600
+1,000
+167% +$16K ﹤0.01% 8207
2021
Q2 		$8K Buy
600
+564
+1,567% +$7.88K ﹤0.01% 9244
2021
Q1 		$52K Buy
36
+27
+300% +$475 ﹤0.01% 6572
2020
Q4 		$17K Buy
+9
New +$140 ﹤0.01% 7089

Other funds holding SPRO

GP
GSK plc London $599M AUM
P
Pfizer New York $239M AUM 232.47% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
Renaissance Technologies
Renaissance Technologies New York $63.9B AUM 45.56% 1-Year Est. Return
AI
Alphabet Inc Mountain View, California $4.02B AUM 215.74% 1-Year Est. Return
Two Sigma Investments
Two Sigma Investments New York $124B AUM 33.93% 1-Year Est. Return
AFM
Anson Funds Management Dallas, Texas $2.29B AUM 370.24% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
Citadel Advisors
Citadel Advisors Miami, Florida $618B AUM 30.34% 1-Year Est. Return

Simplex Trading's SPRO Position: Q1 2026 in Review

Simplex Trading reduced its Spero Therapeutics (SPRO) stake by 15% in Q1 2026, selling an estimated $12.8K and leaving 30,304 shares worth $70.9K. The position accounts for ﹤0.01% of the portfolio, ranked #5479.

Simplex Trading first reported a position in SPRO in Q2 2020 and has held it in 15 quarters since. The position peaked at $87K in Q2 2025. 50 funds tracked by Wall St. Rank hold SPRO as of Q1 2026.

  • Simplex Trading held 30,304 shares of Spero Therapeutics worth $70.9K as of Q1 2026.
  • Simplex Trading sold 5,382 Spero Therapeutics shares in Q1 2026, an estimated $12.8K.
  • Spero Therapeutics made up ﹤0.01% of Simplex Trading's portfolio in Q1 2026, its #5479 holding.
  • Simplex Trading first reported a position in Spero Therapeutics in Q2 2020 and has held it in 15 quarters since.
  • Simplex Trading's Spero Therapeutics position peaked at $87K in Q2 2025.
  • 50 funds tracked by Wall St. Rank held Spero Therapeutics as of Q1 2026.

Based on Simplex Trading's 13F filing for Q1 2026, filed 14 May 2026.