Cliff Asness's UPB Position Overview
Cliff Asness (via Aqr Capital Management LLC) currently holds 544,869 shares of Upstream Bio, Inc. (UPB) worth $3.77 M, representing 0.00% of the portfolio. First purchased in 2025-Q1, this short-term holding has been held for 6 quarters.
Based on 13F filings, Cliff Asness has maintained this position in UPB for several quarters, showing initial confidence in the investment. Largest addition occurred in Q2 2026, adding 472,698 shares.
Analysis based on 13F filings available since 2013 Q2
Cliff Asness's Upstream Bio (UPB) Holding Value Over Time
Track share changes against reported price movement
Quarterly Upstream Bio (UPB) Trades by Cliff Asness
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q2 2026 | +472,698 | Add 654.97% | 544,869 | $6.92 |
| Q1 2026 | +41,668 | Add 136.60% | 72,171 | $9.00 |
| Q4 2025 | +549 | Add 1.83% | 30,503 | $27.15 |
| Q3 2025 | +202 | Add 0.68% | 29,954 | $18.81 |
| Q2 2025 | +10,930 | Add 58.07% | 29,752 | $10.98 |
| Q1 2025 | +18,822 | New Buy | 18,822 | $6.12 |
Cliff Asness's Upstream Bio Investment FAQs
Cliff Asness first purchased Upstream Bio, Inc. (UPB) in Q1 2025, acquiring 18,822 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Cliff Asness has held Upstream Bio, Inc. (UPB) for 6 quarters since Q1 2025.
Cliff Asness's largest addition to Upstream Bio, Inc. (UPB) was in Q2 2026, adding 544,869 shares worth $3.77 M.
According to the latest 13F filing for Q2 2026, Cliff Asness's firm, Aqr Capital Management LLC, owns 544,869 shares of Upstream Bio, Inc. (UPB), valued at approximately $3.77 M.
As of the Q2 2026 filing, Upstream Bio, Inc. (UPB) represents approximately 0.00% of Cliff Asness's publicly disclosed stock portfolio, making it one of their key holdings.
Cliff Asness's peak holding in Upstream Bio, Inc. (UPB) was 544,869 shares, as reported at the end of Q2 2026.