Rock Springs Capital LUNG Position
ExitedRock Springs Capital exited their position in Pulmonx Corporation (LUNG) in Q3 2025, after holding the stock for 11 quarters.
The position was first reported in Q1 2023 and has been tracked across 11 quarterly 13F filings.
1 other tracked fund also holds LUNG.
Short interest stands at 11.3% of float with 4.6 days to cover, indicating significant bearish positioning against the stock.
About Pulmonx Corporation
Pulmonx Corporation, a medical technology company, provides minimally invasive devices for the treatment of chronic obstructive pulmonary diseases. It offers Zephyr Endobronchial Valve, a solution for the treatment of bronchoscopic in adult patients with hyperinflation associated with severe emphysema; and Chartis Pulmonary Assessment System, a balloon catheter and console system with flow and pressure sensors that are used to assess the presence of collateral ventilation. The company also provides StratX Lung Analysis Platform, a cloud-based quantitative computed tomography analysis service that offers information on emphysema destruction, fissure completeness, and lobar volume to help identify target lobes for the treatment with Zephyr Valves. It serves emphysema patients in the United States, Europe, the Middle East, Africa, the Asia-Pacific, and internationally. The company was formerly known as Pulmonx and changed its name to Pulmonx Corporation in December 2013. Pulmonx Corporation was incorporated in 1995 and is headquartered in Redwood City, California.
Full company profile →Short Interest
11.3%
4.6 days to cover
Rock Springs Capital LUNG Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q3 2025 | Exited | 0 | -651,100 | $0 |
| Q2 2025 | Increased | 651,100 | +147,400 | $1.7M |
| Q1 2025 | Decreased | 503,700 | -268,451 | $3.4M |
| Q4 2024 | Increased | 772,151 | +80,851 | $5.2M |
| Q3 2024 | Increased | 691,300 | +38,900 | $5.7M |
| Q2 2024 | Held | 652,400 | — | $4.1M |
| Q1 2024 | Held | 652,400 | — | $6.0M |
| Q4 2023 | Held | 652,400 | — | $8.3M |
| Q3 2023 | Held | 652,400 | — | $6.7M |
| Q2 2023 | Held | 652,400 | — | $8.6M |
| Q1 2023 | New | 652,400 | +652,400 | $7.3M |
Frequently Asked Questions
Does Rock Springs Capital own LUNG?
No. Rock Springs Capital exited their position in Pulmonx Corporation (LUNG) in Q3 2025. They previously held the stock for 11 quarters.
How many hedge funds own LUNG?
1 specialist biotech hedge fund currently holds LUNG, including Deerfield Management. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Rock Springs Capital first buy LUNG?
Rock Springs Capital's position in LUNG 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 LUNG position increasing or decreasing?
Rock Springs Capital completely exited their LUNG position in the most recent quarter.
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