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Ironwood Pharmaceuticals Inc. short interest

15.9M shares of Ironwood Pharmaceuticals were sold short at the 15 October 2026 settlement, near the top of its range over the last year (4.7M to 18.7M). Short sellers would need 8.0 days of normal trading to buy them back.

Shares sold short15.9Mat 15 Oct 2026
Change on the settlement before+2.1%+238% over a year
Days to cover7.99at 2.0M shares a day
Of shares in issue9.61%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 near the top of its range over the last year (4.7M to 18.7M), and the share price moved +125% 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

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    Every settlement since 29 Dec 2017 as a table
    SettlementShares shortChangeAverage daily volumeDays to cover
    15 October 202615.9M+2.1%2.0M7.99
    30 September 202615.6M-16.9%2.5M6.19
    15 September 202618.7M+6.1%1.4M13.11
    31 August 202617.7M-2.3%1.5M11.90
    14 August 202618.1M+9.2%2.8M6.44
    31 July 202616.5M-3.8%1.6M10.04
    15 July 202617.2M+5.9%2.7M6.32
    30 June 202616.2M+2.1%2.9M5.65
    15 June 202615.9M+5.9%1.9M8.18
    29 May 202615.0M-13.4%2.5M6.00
    15 May 202617.3M+0.4%3.0M5.77
    30 April 202617.3M-5.1%1.6M10.51
    15 April 202618.2M+1.6%1.8M10.20
    31 March 202617.9M+30.7%3.8M4.67
    13 March 202613.7M+6.1%2.1M6.65
    27 February 202612.9M+15.8%4.0M3.24
    13 February 202611.2M+17.9%2.5M4.52
    30 January 20269.5M+5.1%2.7M3.52
    15 January 20269.0M+10.6%12.4M1.00
    31 December 20258.1M+11.2%2.5M3.22
    15 December 20257.3M-1.8%1.9M3.79
    28 November 20257.5M+4.3%2.7M2.75
    14 November 20257.2M+50.2%4.8M1.48
    31 October 20254.8M+1.3%1.2M4.03
    15 October 20254.7M-9.0%1.3M3.60
    30 September 20255.2M-9.5%1.4M3.67
    15 September 20255.7M-5.9%1.3M4.32
    29 August 20256.1M-0.1%1.2M5.14
    15 August 20256.1M+12.8%1.7M3.66
    31 July 20255.4M-17.6%1.3M4.23
    15 July 20256.5M-12.7%1.2M5.24
    30 June 20257.5M-2.3%2.2M3.41
    13 June 20257.7M-7.0%3.3M2.35
    30 May 20258.2M-2.9%3.4M2.39
    15 May 20258.5M-3.8%2.4M3.59
    30 April 20258.8M-24.4%3.1M2.88
    15 April 202511.6M+3.5%5.2M2.25
    31 March 202511.3M-30.8%3.1M3.59
    14 March 202516.2M+34.8%2.6M6.26
    28 February 202512.1M+12.6%2.4M5.08
    14 February 202510.7M-0.5%6.7M1.59
    31 January 202510.8M+13.8%2.4M4.45
    15 January 20259.4M+2.5%2.1M4.48
    31 December 20249.2M-23.7%2.8M3.25
    13 December 202412.1M+7.7%1.9M6.31
    29 November 202411.2M+30.9%1.7M6.42
    15 November 20248.6M-21.8%1.6M5.41
    31 October 202411.0M-8.2%1.1M10.31
    15 October 202411.9M+1.2%1.2M9.79
    30 September 202411.8M+1.5%1.9M6.19
    13 September 202411.6M-14.6%2.2M5.28
    30 August 202413.6M-2.9%1.6M8.38
    15 August 202414.0M-11.4%3.1M4.54
    31 July 202415.8M-6.2%1.5M10.69
    15 July 202416.8M-6.7%1.5M11.21
    28 June 202418.1M-10.6%3.5M5.17
    14 June 202420.2M-10.8%2.7M7.50
    31 May 202422.7M+0.8%2.1M10.86
    15 May 202422.5M+12.0%3.0M7.38
    30 April 202420.1M-5.1%2.6M7.66
    15 April 202421.2M-3.6%2.5M8.63
    28 March 202422.0M+16.9%3.6M6.15
    15 March 202418.8M+21.0%9.1M2.06
    29 February 202415.5M-0.5%5.7M2.71
    15 February 202415.6M+7.9%3.5M4.50
    31 January 202414.5M-10.1%4.4M3.29
    12 January 202416.1M+2.1%2.5M6.39
    29 December 202315.8M-7.3%1.5M10.75
    15 December 202317.0M+2.3%2.6M6.50
    30 November 202316.6M-3.1%1.7M9.69
    15 November 202317.2M-1.4%2.2M7.64
    31 October 202317.4M-0.8%2.1M8.18
    13 October 202317.5M-0.6%2.0M8.72
    29 September 202317.6M+20.3%3.3M5.40
    15 September 202314.7M-5.4%3.5M4.21
    31 August 202315.5M+3.9%2.5M6.09
    15 August 202314.9M-1.8%2.3M6.44
    31 July 202315.2M-6.5%1.5M10.06
    14 July 202316.3M+13.5%1.8M9.05
    30 June 202314.3M-17.9%2.4M5.99
    15 June 202317.4M-1.0%1.9M9.25
    31 May 202317.6M+6.4%2.7M6.57
    15 May 202316.6M-3.3%1.9M8.63
    28 April 202317.1M-14.9%2.1M8.22
    14 April 202320.1M+14.2%3.7M5.45
    31 March 202317.6M+8.0%2.5M7.20
    15 March 202316.3M+1.0%1.8M8.92
    28 February 202316.2M+1.4%2.6M6.31
    15 February 202315.9M-0.2%2.0M8.15
    31 January 202316.0M+0.1%1.9M8.50
    13 January 202315.9M-2.6%2.0M7.83
    30 December 202216.4M-3.4%1.7M9.50
    15 December 202216.9M+2.8%1.7M10.26
    30 November 202216.5M-12.4%1.3M12.33
    15 November 202218.8M+9.7%2.3M8.25
    31 October 202217.1M-1.5%1.9M9.03
    14 October 202217.4M+0.2%2.0M8.61
    30 September 202217.4M-3.3%2.6M6.74
    15 September 202218.0M-1.1%2.3M7.89
    31 August 202218.2M-0.4%1.8M10.12
    15 August 202218.2M+0.9%2.8M6.46
    29 July 202218.1M+3.3%2.3M8.00
    15 July 202217.5M-6.1%2.2M8.08
    30 June 202218.6M+32.4%6.8M2.74
    15 June 202214.1M-4.1%3.7M3.82
    31 May 202214.7M-7.7%2.7M5.46
    13 May 202215.9M-2.8%2.4M6.55
    29 April 202216.4M-3.2%2.0M8.04
    14 April 202216.9M+5.3%2.3M7.45
    31 March 202216.0M+6.2%2.6M6.20
    15 March 202215.1M+22.2%2.4M6.31
    28 February 202212.4M-6.5%3.2M3.86
    15 February 202213.2M-17.7%2.7M4.97
    31 January 202216.1M-3.7%3.2M5.03
    14 January 202216.7M-2.1%1.9M8.98
    31 December 202117.0M-7.1%1.7M10.30
    15 December 202118.3M-11.3%2.3M7.90
    30 November 202120.7M-1.5%2.3M9.06
    15 November 202121.0M-7.0%2.1M9.81
    29 October 202122.5M+10.4%2.0M11.26
    15 October 202120.4M-0.0%1.7M11.99
    30 September 202120.4M+1.9%2.0M10.09
    15 September 202120.0M-4.1%1.7M11.82
    31 August 202120.9M+0.2%1.5M14.00
    13 August 202120.9M+2.3%1.6M13.25
    30 July 202120.4M+4.2%1.9M10.92
    15 July 202119.6M-1.9%2.0M9.96
    30 June 202119.9M-3.7%2.6M7.67
    15 June 202120.7M+11.1%1.9M11.13
    28 May 202118.6M-4.3%1.5M12.36
    14 May 202119.5M+6.4%1.7M11.52
    30 April 202118.3M+0.9%1.2M15.12
    15 April 202118.1M-6.9%1.6M11.07
    31 March 202119.5M-5.0%1.9M10.38
    15 March 202120.5M+14.5%3.5M5.82
    26 February 202117.9M-1.4%1.8M10.04
    12 February 202118.2M+5.5%1.6M11.71
    29 January 202117.2M-5.7%2.1M8.05
    15 January 202118.3M-0.4%1.0M17.51
    31 December 202018.3M-7.0%1,000K18.34
    15 December 202019.7M-3.6%1.4M14.35
    30 November 202020.4M+0.3%852K24.00
    13 November 202020.4M-7.9%2.8M7.38
    30 October 202022.1M+5.0%1.7M12.86
    15 October 202021.1M+2.3%2.7M7.80
    30 September 202020.6M-1.0%1.6M12.74
    15 September 202020.8M-2.5%1.1M19.56
    31 August 202021.3M-13.4%1.5M13.93
    14 August 202024.6M+3.8%1.6M15.20
    31 July 202023.7M-4.5%2.1M11.18
    15 July 202024.8M-6.5%1.2M21.01
    30 June 202026.6M+5.7%2.0M13.46
    15 June 202025.1M+3.6%2.9M8.81
    29 May 202024.2M-3.7%2.0M11.99
    15 May 202025.2M+0.6%1.8M14.18
    30 April 202025.0M-4.3%1.5M16.62
    15 April 202026.1M-3.9%1.6M16.72
    31 March 202027.2M-2.8%2.0M13.74
    13 March 202028.0M-3.3%1.9M14.63
    28 February 202029.0M+0.9%2.6M11.02
    14 February 202028.7M+0.1%1.4M20.92
    31 January 202028.7M-0.7%1.2M23.02
    15 January 202028.9M+0.7%2.4M12.14
    31 December 201928.7M+4.7%1.4M20.19
    13 December 201927.4M+1.5%1.6M17.11
    29 November 201927.0M+5.9%1.6M16.89
    15 November 201925.5M-1.5%1.5M17.09
    31 October 201925.8M-0.9%1.2M21.29
    15 October 201926.1M-3.1%1.3M20.08
    30 September 201926.9M+0.3%1.9M13.90
    13 September 201926.9M+5.5%2.9M9.42
    30 August 201925.5M+3.3%1.5M17.52
    15 August 201924.6M+31.5%3.0M8.30
    31 July 201918.7M-4.2%1.5M12.88
    15 July 201919.6M+10.5%991K19.74
    28 June 201917.7M+4.0%1.6M10.79
    14 June 201917.0M+1.0%1.1M15.81
    31 May 201916.8M+13.4%1.5M11.22
    15 May 201914.9M-3.0%1.8M8.04
    30 April 201915.3M+6.8%1.2M13.22
    15 April 201914.3M+0.6%1.3M10.71
    29 March 201914.2M-0.1%1.4M9.85
    15 March 201914.3M-1.8%1.2M11.45
    28 February 201914.5M-2.5%1.2M12.34
    15 February 201914.9M+1.1%2.1M6.97
    31 January 201914.7M+5.3%1.6M9.49
    15 January 201914.0M+10.0%1.4M9.73
    31 December 201812.7M+2.9%1.2M10.73
    14 December 201812.4M-5.2%1.9M6.41
    30 November 201813.0M+5.7%1.3M10.31
    15 November 201812.3M-19.6%2.0M6.22
    31 October 201815.3M+6.3%1.7M9.01
    15 October 201814.4M+3.5%1.1M12.67
    28 September 201813.9M-8.2%753K18.52
    14 September 201815.2M+0.6%795K19.11
    31 August 201815.1M-1.6%624K24.21
    15 August 201815.3M-4.1%898K17.07
    31 July 201816.0M-8.2%1.1M14.98
    13 July 201817.4M-4.5%1.0M16.96
    29 June 201818.2M-3.9%1.3M14.03
    15 June 201819.0M+5.9%1.4M13.90
    31 May 201817.9M-4.8%1.3M13.73
    15 May 201818.8M-12.2%1.7M11.09
    30 April 201821.4M-1.6%1.5M14.01
    13 April 201821.8M-1.0%1.7M12.48
    29 March 201822.0M+2.5%1.1M20.48
    15 March 201821.5M+3.7%933K23.04
    28 February 201820.7M+7.6%1.3M15.51
    15 February 201819.3M+0.7%1.5M12.45
    31 January 201819.1M+2.8%2.3M8.19
    12 January 201818.6M+2.3%1.8M10.28
    29 December 201718.2M819K22.23
    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.