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Heartflow, Inc. short interest

7.3M shares of Heartflow were sold short at the 15 October 2026 settlement, the most at any settlement since 15 Aug 2025, when our record starts. Short sellers would need 4.4 days of normal trading to buy them back.

Shares sold short7.3Mat 15 Oct 2026
Change on the settlement before+7.5%+1726% over a year
Days to cover4.42at 1.7M shares a day
Of shares in issue8.45%shares short over shares outstanding
New to this? How to read this page
  1. Short interest is the number of shares investors have borrowed and sold, betting the price will fall, and not yet bought back.
  2. Days to cover is shares short over an average day's trading: how many days it would take short sellers to buy them all back. Above 5 or so is high.
  3. Rising short interest says more investors are betting against the stock. A crowded short can also rise fast if shorts rush to buy back.
  4. Brokers report it twice a month to FINRA, about ten days after each settlement date.
  5. What is short interest?

Short interest, days to cover and the price

Short interest is the most at any settlement since 15 Aug 2025, when our record starts, and the share price moved +68% over the last year.

Shares sold shortDays to coverShare price

Three charts on one timeline. Top: shares sold short at each settlement. Middle: days to cover, taller meaning shorts would need longer to buy back. Bottom: the share price, so you can see whether shorts added as the price fell or rose.

How it compares

every company on the site

    The bar ranks every company on the site from the lowest on the left to the highest on the right, in three equal thirds; the small figures under it are the values where each third starts, and the black tick is the middle company. The orange dot is this company; the grey ticks are the other companies in its industry (hover or tap for names). A hatched block is companies tied at none.

    Every settlement since 15 Aug 2025 as a table
    SettlementShares shortChangeAverage daily volumeDays to cover
    15 October 20267.3M+7.5%1.7M4.42
    30 September 20266.8M+21.1%2.0M3.34
    15 September 20265.6M-7.3%1.8M3.07
    31 August 20266.1M-10.5%2.4M2.54
    14 August 20266.8M-1.0%1.8M3.85
    31 July 20266.8M+16.6%1.0M6.61
    15 July 20265.9M+13.4%1.4M4.15
    30 June 20265.2M+22.9%3.0M1.74
    15 June 20264.2M+15.9%1.1M3.67
    29 May 20263.6M+4.5%1.3M2.90
    15 May 20263.5M-20.2%1.1M3.31
    30 April 20264.4M-21.4%1.1M3.88
    15 April 20265.5M-7.7%1.2M4.60
    31 March 20266.0M+8.1%2.0M3.05
    13 March 20265.6M+2.0%1.1M5.15
    27 February 20265.5M+19.6%1.2M4.39
    13 February 20264.6M-7.9%2.8M1.65
    30 January 20265.0M+42.4%843K5.87
    15 January 20263.5M+9.9%830K4.19
    31 December 20253.2M+118.3%1.0M3.06
    15 December 20251.4M+18.8%503K2.88
    28 November 20251.2M+10.7%695K1.76
    14 November 20251.1M+127.6%500K2.21
    31 October 2025484K+20.6%242K2.00
    15 October 2025401K-47.6%385K1.04
    30 September 2025767K+28.6%448K1.71
    15 September 2025596K+9.3%323K1.85
    29 August 2025545K+17.7%360K1.51
    15 August 2025463K1.1M1.00
    Shares in millions (M) or thousands (K); hold the pointer on a figure for the exact count. FINRA publishes consolidated short interest twice a month, about ten days after each settlement.