Renaissance Technologies (RenTech)'s SPRO Position Overview
Renaissance Technologies (RenTech) (via Renaissance Technologies LLC) currently holds 947,904 shares of Spero Therapeutics, Inc. (SPRO) worth $2.09 M, representing 0.00% of the portfolio. First purchased in 2018-Q3, this long-term strategic position has been held for 28 quarters.
Based on 13F filings, Renaissance Technologies (RenTech) has maintained a strategic position in SPRO, demonstrating sustained confidence in this investment. Largest addition occurred in Q2 2022, adding 829,917 shares. Largest reduction occurred in Q3 2022, reducing 724,317 shares.
Analysis based on 13F filings available since 2013 Q2
Renaissance Technologies (RenTech)'s Spero Therapeutics (SPRO) Holding Value Over Time
Track share changes against reported price movement
Quarterly Spero Therapeutics (SPRO) Trades by Renaissance Technologies (RenTech)
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q2 2026 | -241,331 | Reduce 20.29% | 947,904 | $2.21 |
| Q1 2026 | -90,287 | Reduce 7.06% | 1.19 M | $2.34 |
| Q4 2025 | -173,243 | Reduce 11.93% | 1.28 M | $2.33 |
| Q3 2025 | +620,600 | Add 74.58% | 1.45 M | $1.88 |
| Q2 2025 | -138,742 | Reduce 14.29% | 832,165 | $2.90 |
| Q1 2025 | -134,684 | Reduce 12.18% | 970,907 | $0.72 |
| Q4 2024 | +130,938 | Add 13.43% | 1.11 M | $1.03 |
| Q3 2024 | -1,299 | Reduce 0.13% | 974,653 | $1.34 |
| Q2 2024 | +121,492 | Add 14.22% | 975,952 | $1.30 |
| Q1 2024 | +306,995 | Add 56.08% | 854,460 | $1.72 |
| Q4 2023 | +300 | Add 0.05% | 547,465 | $1.47 |
| Q3 2023 | -46,266 | Reduce 7.80% | 547,165 | $1.21 |
| Q2 2023 | +183,131 | Add 44.63% | 593,431 | $0.00 |
| Q1 2023 | +67,400 | Add 19.66% | 410,300 | $0.00 |
| Q4 2022 | +128,200 | Add 59.71% | 342,900 | $0.00 |
| Q3 2022 | -724,317 | Reduce 77.14% | 214,700 | $2.00 |
| Q2 2022 | +829,917 | Add 760.69% | 939,017 | $0.74 |
| Q1 2022 | +109,100 | New Buy | 109,100 | $8.70 |
| Q4 2020 | -153,203 | Sold Out | 0 | $0.00 |
| Q3 2020 | -176,700 | Reduce 53.56% | 153,203 | $11.16 |
| Q2 2020 | +5,600 | Add 1.73% | 329,903 | $13.53 |
| Q1 2020 | -13,900 | Reduce 4.11% | 324,303 | $8.08 |
| Q4 2019 | +85,400 | Add 33.78% | 338,203 | $9.62 |
| Q3 2019 | +37,900 | Add 17.64% | 252,803 | $10.60 |
| Q2 2019 | +101,600 | Add 89.67% | 214,903 | $11.51 |
| Q1 2019 | +70,400 | Add 164.09% | 113,303 | $12.81 |
| Q4 2018 | +30,903 | Add 257.52% | 42,903 | $6.15 |
| Q3 2018 | +12,000 | New Buy | 12,000 | $10.50 |
Renaissance Technologies (RenTech)'s Spero Therapeutics Investment FAQs
Renaissance Technologies (RenTech) first purchased Spero Therapeutics, Inc. (SPRO) in Q3 2018, acquiring 12,000 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies (RenTech) has held Spero Therapeutics, Inc. (SPRO) for 28 quarters since Q3 2018.
Renaissance Technologies (RenTech)'s largest addition to Spero Therapeutics, Inc. (SPRO) was in Q2 2022, adding 939,017 shares worth $696,000.
According to the latest 13F filing for Q2 2026, Renaissance Technologies (RenTech)'s firm, Renaissance Technologies LLC, owns 947,904 shares of Spero Therapeutics, Inc. (SPRO), valued at approximately $2.09 M.
As of the Q2 2026 filing, Spero Therapeutics, Inc. (SPRO) represents approximately 0.00% of Renaissance Technologies (RenTech)'s publicly disclosed stock portfolio, making it one of their key holdings.
Renaissance Technologies (RenTech)'s peak holding in Spero Therapeutics, Inc. (SPRO) was 1,452,765 shares, as reported at the end of Q3 2025.