Rock Springs Capital ZLAB Position
Active4-Fund ConvergenceRock Springs Capital increased their position in Zai Lab Ltd (ZLAB) in Q4 2025, holding $14.3M worth of shares across 811,546 shares.
The position was first reported in Q1 2023 and has been tracked across 12 quarterly 13F filings.
ZLAB is a convergence signal: 4 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 3 readout for ZL-1109 (VRDN-003) in 332 days (Mar 14, 2027), making the timing of Rock Springs's position particularly relevant.
About Zai Lab Ltd
Zai Lab Limited develops and commercializes therapies to treat oncology, autoimmune disorders, infectious diseases, and neuroscience primarily in Mainland China and Hong Kong. The company's commercial products include Zejula, a once-daily small-molecule poly polymerase 1/2 inhibitor; Optune, a device that delivers tumor treating fields; NUZYRA for acute bacterial skin and skin structure infections, and community acquired bacterial pneumonia; and Qinlock to treat gastrointestinal stromal tumors. It also develops Odronextamab to treat follicular lymphoma, diffuse large B-cell lymphoma, and other B-celllymphomas; Repotrectinib, a tyrosine kinase inhibitor (TKI) to target ROS1 and TRK A/B/C in TKI-naïve- or -pretreated cancer patients; Margetuximab for the treatment of breast and gastroesophageal cancers; Adagrasib for treating KRAS-G12C-mutated NSCLC, colorectal cancer, pancreatic cancer, and other solid tumors; and Bemarituzumab to treat gastric and gastroesophageal junction cancer. In addition, the company develops CLN-081 for the treatment of patients with EGFR exon 20 insertion NSCLC; Elzovantinib, an orally bioavailable multi-targeted kinase inhibitor; Tebotelimab, a tetravalent IgG4 monoclonal antibody; Retifanlimab that inhibits interactions between PD-1 and its ligands; ZL-2309, an orally active, selective, and ATP-competitive cell division cycle 7 (CDC7) kinase inhibitor; ZL-1201, a humanized IgG4 monoclonal antibody; Efgartigimod to reduce disease-causing immunoglobulin G antibodies; ZL-1102, a human nanobody targeting interleukin- 17A; KarXT for the treatment of psychiatric and neurological conditions; ZL-2313, an investigational inhibitor of triple-mutant EGFR harboring; ZL-2314, an investigational inhibitor of double-mutant EGFR harboring; and Sulbactam/durlobactam for the treatment of serious infections caused by Acinetobacter. Zai Lab Limited was incorporated in 2013 and is headquartered in Shanghai, China.
Full company profile →Short Interest
4.9%
8.4 days to cover
Rock Springs Capital ZLAB Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q4 2025 | Increased | 811,546 | +20,353 | $14.3M |
| Q3 2025 | Decreased | 791,193 | -80,199 | $26.8M |
| Q2 2025 | Decreased | 871,392 | -33,200 | $30.5M |
| Q1 2025 | Decreased | 904,592 | -400,745 | $32.7M |
| Q4 2024 | Decreased | 1,305,337 | -10,336 | $34.2M |
| Q3 2024 | Increased | 1,315,673 | +17,800 | $31.8M |
| Q2 2024 | Increased | 1,297,873 | +750 | $22.5M |
| Q1 2024 | Increased | 1,297,123 | +160,100 | $20.8M |
| Q4 2023 | Decreased | 1,137,023 | -100,000 | $31.1M |
| Q3 2023 | Increased | 1,237,023 | +14,600 | $30.1M |
| Q2 2023 | Increased | 1,222,423 | +162,723 | $33.9M |
| Q1 2023 | New | 1,059,700 | +1,059,700 | $35.2M |
Frequently Asked Questions
Does Rock Springs Capital own ZLAB?
Yes. As of Q4 2025, Rock Springs Capital holds 811,546 shares of Zai Lab Ltd (ZLAB) valued at $14.3M. This data comes from their SEC 13F filing.
How many hedge funds own ZLAB?
4 specialist biotech hedge funds currently hold ZLAB, including RTW Investments, RA Capital Management, OrbiMed Advisors. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Rock Springs Capital first buy ZLAB?
Rock Springs Capital's position in ZLAB was first reported in Q1 2023. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is Rock Springs Capital's ZLAB position increasing or decreasing?
Rock Springs Capital increased their ZLAB position in the most recent quarter, adding 20,353 shares.
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