About Masimo Corporation (MASI) data
Data as of May 29, 2026.
Masimo Corporation (MASI) has 3.50M shares sold short as of the latest FINRA settlement report on May 29, 2026. Short interest has decreased by 6.13% compared with the prior settlement. At the current average daily volume, covering all open short positions would take about 3.65 days (days to cover).
Recent MASI short interest history
| Settlement date | Short interest | Change | Days to cover |
|---|---|---|---|
| May 29, 2026 | 3,501,739 | -6.13% | 3.65 |
| May 15, 2026 | 3,730,274 | -3.97% | 4.28 |
| Apr 30, 2026 | 3,884,472 | 1.72% | 6.06 |
| Apr 15, 2026 | 3,818,925 | 17.58% | 5.47 |
| Mar 31, 2026 | 3,248,048 | 21.16% | 1.68 |
| Mar 13, 2026 | 2,680,885 | -29.97% | 1.45 |
| Feb 27, 2026 | 3,828,135 | -3.87% | 1.00 |
| Feb 13, 2026 | 3,982,220 | -3.16% | 6.15 |
| Jan 30, 2026 | 4,112,256 | -0.41% | 5.16 |
| Jan 15, 2026 | 4,129,092 | 5.15% | 5.50 |
| Dec 31, 2025 | 3,926,750 | -1.06% | 5.52 |
| Dec 15, 2025 | 3,968,788 | 3.86% | 4.83 |
Full history, charts, and borrow-fee detail are on the MASI short interest page.
Frequently asked questions
What is the current short interest in MASI?
As of the latest FINRA settlement dated May 29, 2026, MASI had approximately 3,501,739 shares sold short. Short interest data is reported by FINRA twice per month.
How much does it cost to short MASI?
The latest borrow fee (cost to borrow) for MASI is 0.25% per year, based on IBKR data. Fees can change throughout the trading day as shares are borrowed and returned.
What is the days to cover ratio for MASI?
Days to cover for MASI is approximately 3.65 days. This estimates how many trading days it would take short sellers to buy back all outstanding short shares at the current average daily volume.
Is MASI a short squeeze candidate?
A squeeze needs shorts that are hard to close. MASI trades about 958,552 shares a day and would take roughly 3.65 days to unwind current short positions, at a current borrow fee of 0.25%. Higher days-to-cover and a rising borrow fee together are the setup to watch; neither alone is enough.