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Align Technology Inc. short interest

4.1M shares of Align Technology were sold short at the 15 October 2026 settlement, near the middle of its range over the last year (1.9M to 4.9M). Short sellers would need 4.3 days of normal trading to buy them back.

Shares sold short4.1Mat 15 Oct 2026
Change on the settlement before-1.3%+71% over a year
Days to cover4.33at 958K shares a day
Of shares in issue5.87%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 middle of its range over the last year (1.9M to 4.9M), and the share price moved +29% 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

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    Every settlement since 29 Dec 2017 as a table
    SettlementShares shortChangeAverage daily volumeDays to cover
    15 October 20264.1M-1.3%958K4.33
    30 September 20264.2M+7.7%977K4.30
    15 September 20263.9M+1.2%797K4.89
    31 August 20263.9M+12.5%877K4.40
    14 August 20263.4M-18.5%793K4.32
    31 July 20264.2M-12.9%1.1M3.97
    15 July 20264.8M+3.1%902K5.35
    30 June 20264.7M-0.6%1.2M3.88
    15 June 20264.7M+1.8%917K5.14
    29 May 20264.6M-5.9%1.2M3.80
    15 May 20264.9M+15.4%774K6.36
    30 April 20264.3M+11.7%1.2M3.47
    15 April 20263.8M-12.3%869K4.39
    31 March 20264.4M+46.8%1.3M3.30
    13 March 20263.0M+25.5%1.4M2.08
    27 February 20262.4M-0.0%1.0M2.26
    13 February 20262.4M+22.4%1.8M1.30
    30 January 20261.9M+1.4%825K2.34
    15 January 20261.9M-19.6%909K2.09
    31 December 20252.4M-19.2%998K2.37
    15 December 20252.9M+15.3%1.4M2.04
    28 November 20252.5M-15.3%1.9M1.33
    14 November 20253.0M+16.2%1.1M2.81
    31 October 20252.6M+6.3%1.4M1.82
    15 October 20252.4M+13.6%1.3M1.93
    30 September 20252.1M-4.2%1.2M1.78
    15 September 20252.2M+2.5%1.3M1.67
    29 August 20252.2M-5.5%1.2M1.78
    15 August 20252.3M-15.9%2.4M1.00
    31 July 20252.7M+0.1%2.0M1.34
    15 July 20252.7M-2.4%887K3.09
    30 June 20252.8M-7.0%959K2.92
    13 June 20253.0M-1.1%668K4.52
    30 May 20253.0M+2.1%814K3.75
    15 May 20253.0M-6.5%1.2M2.58
    30 April 20253.2M-13.6%1.3M2.40
    15 April 20253.7M+7.4%1.5M2.49
    31 March 20253.4M-9.7%1.1M3.11
    14 March 20253.8M+0.9%1.5M2.49
    28 February 20253.8M+31.0%1.0M3.70
    14 February 20252.9M+27.6%1.1M2.61
    31 January 20252.3M-3.5%656K3.44
    15 January 20252.3M-13.5%593K3.95
    31 December 20242.7M+1.8%719K3.77
    13 December 20242.7M+5.0%547K4.86
    29 November 20242.5M-15.4%793K3.20
    15 November 20243.0M+3.3%810K3.70
    31 October 20242.9M-3.0%1.1M2.66
    15 October 20243.0M-3.2%640K4.67
    30 September 20243.1M+5.0%693K4.46
    13 September 20242.9M+7.7%593K4.96
    30 August 20242.7M+0.1%602K4.54
    15 August 20242.7M+21.6%925K2.95
    31 July 20242.2M+6.5%995K2.25
    15 July 20242.1M+4.7%628K3.36
    28 June 20242.0M+9.3%968K2.08
    14 June 20241.8M+19.9%883K2.09
    31 May 20241.5M+2.3%753K2.04
    15 May 20241.5M+16.2%577K2.60
    30 April 20241.3M-6.5%739K1.75
    15 April 20241.4M-1.9%612K2.26
    28 March 20241.4M-0.9%433K3.25
    15 March 20241.4M-14.1%531K2.67
    29 February 20241.7M-5.1%669K2.47
    15 February 20241.7M+19.5%1.3M1.37
    31 January 20241.5M-8.8%846K1.72
    12 January 20241.6M-18.2%777K2.06
    29 December 20232.0M-29.6%767K2.55
    15 December 20232.8M-7.5%1.7M1.62
    30 November 20233.0M+2.1%961K3.12
    15 November 20232.9M-16.8%1.4M2.06
    31 October 20233.5M+47.4%1.6M2.27
    13 October 20232.4M+13.9%705K3.39
    29 September 20232.1M+5.7%604K3.48
    15 September 20232.0M-4.5%658K3.02
    31 August 20232.1M-8.2%507K4.10
    15 August 20232.3M-0.3%497K4.56
    31 July 20232.3M-11.0%1.3M1.78
    14 July 20232.6M-6.7%590K4.32
    30 June 20232.7M+8.8%670K4.08
    15 June 20232.5M-3.5%630K3.99
    31 May 20232.6M+42.3%699K3.73
    15 May 20231.8M-20.7%672K2.72
    28 April 20232.3M-4.7%937K2.46
    14 April 20232.4M+3.8%602K4.02
    31 March 20232.3M-12.5%872K2.67
    15 March 20232.7M+9.7%1.0M2.54
    28 February 20232.4M-14.1%828K2.94
    15 February 20232.8M+34.9%1.5M1.84
    31 January 20232.1M-8.9%1.1M2.00
    13 January 20232.3M+31.8%894K2.58
    30 December 20221.7M-20.4%977K1.79
    15 December 20222.2M-8.7%940K2.34
    30 November 20222.4M-4.7%791K3.04
    15 November 20222.5M-8.7%1.3M1.92
    31 October 20222.8M+18.6%1.4M1.94
    14 October 20222.3M-9.7%787K2.96
    30 September 20222.6M+24.5%1.1M2.34
    15 September 20222.1M-4.9%705K2.94
    31 August 20222.2M-4.6%647K3.37
    15 August 20222.3M-3.5%699K3.27
    29 July 20222.4M-12.8%1.2M2.04
    15 July 20222.7M+4.2%713K3.81
    30 June 20222.6M+15.3%1.4M1.90
    15 June 20222.3M+30.8%1.0M2.26
    31 May 20221.7M+1.0%1.1M1.60
    13 May 20221.7M+30.1%1.3M1.27
    29 April 20221.3M-10.1%1.3M1.00
    14 April 20221.5M+2.4%569K2.57
    31 March 20221.4M-13.2%743K1.92
    15 March 20221.6M-7.5%964K1.71
    28 February 20221.8M-1.9%629K2.83
    15 February 20221.8M+7.4%1.1M1.63
    31 January 20221.7M+9.4%1.1M1.58
    14 January 20221.5M+23.7%916K1.69
    31 December 20211.2M+13.8%466K2.68
    15 December 20211.1M-14.3%557K1.97
    30 November 20211.3M-17.6%474K2.70
    15 November 20211.6M+24.3%559K2.78
    29 October 20211.3M-9.6%946K1.32
    15 October 20211.4M-1.5%643K2.15
    30 September 20211.4M-18.3%509K2.76
    15 September 20211.7M+1.0%464K3.71
    31 August 20211.7M+3.2%444K3.84
    13 August 20211.7M+0.8%540K3.05
    30 July 20211.6M+16.9%664K2.47
    15 July 20211.4M-8.4%539K2.60
    30 June 20211.5M-25.0%743K2.06
    15 June 20212.0M-4.8%445K4.59
    28 May 20212.1M+9.5%483K4.44
    14 May 20212.0M+13.5%646K3.03
    30 April 20211.7M-12.4%469K3.68
    15 April 20212.0M+12.1%513K3.84
    31 March 20211.8M+6.9%598K2.94
    15 March 20211.6M+23.6%761K2.16
    26 February 20211.3M+3.7%481K2.76
    12 February 20211.3M-1.6%643K1.99
    29 January 20211.3M-5.0%518K2.52
    15 January 20211.4M+1.3%364K3.77
    31 December 20201.4M-6.1%353K3.84
    15 December 20201.4M-13.6%497K2.90
    30 November 20201.7M-16.3%456K3.66
    13 November 20202.0M-1.1%739K2.70
    30 October 20202.0M-22.4%1.2M1.62
    15 October 20202.6M-6.3%492K5.28
    30 September 20202.8M-14.9%545K5.09
    15 September 20203.3M+5.6%734K4.45
    31 August 20203.1M-8.4%484K6.39
    14 August 20203.4M+3.7%564K5.98
    31 July 20203.3M-8.5%824K3.95
    15 July 20203.6M-3.1%672K5.29
    30 June 20203.7M-3.6%745K4.93
    15 June 20203.8M-21.2%1.1M3.39
    29 May 20204.8M-7.3%1.0M4.65
    15 May 20205.2M+3.6%1.0M5.17
    30 April 20205.0M-0.5%1.1M4.45
    15 April 20205.1M+30.9%1.3M3.94
    31 March 20203.9M+8.8%1.5M2.62
    13 March 20203.5M-2.7%1.1M3.17
    28 February 20203.6M+1.5%944K3.86
    14 February 20203.6M+2.5%732K4.91
    31 January 20203.5M+2.3%935K3.75
    15 January 20203.4M-8.9%658K5.21
    31 December 20193.8M-4.4%518K7.26
    13 December 20193.9M+2.2%504K7.82
    29 November 20193.9M-1.5%573K6.72
    15 November 20193.9M+0.1%682K5.73
    31 October 20193.9M+1.7%1.3M3.01
    15 October 20193.8M-2.0%1.1M3.61
    30 September 20193.9M-6.5%1.2M3.24
    13 September 20194.2M+11.8%1.6M2.68
    30 August 20193.7M+2.1%999K3.75
    15 August 20193.7M-2.3%1.4M2.61
    31 July 20193.8M+2.6%2.3M1.60
    15 July 20193.7M-0.4%709K5.16
    28 June 20193.7M+23.9%1.3M2.88
    14 June 20193.0M+4.9%766K3.87
    31 May 20192.8M+6.8%973K2.90
    15 May 20192.6M-3.8%916K2.89
    30 April 20192.7M-1.7%1.5M1.80
    15 April 20192.8M-8.2%914K3.06
    29 March 20193.0M+7.2%1.2M2.48
    15 March 20192.8M+1.7%1.8M1.57
    28 February 20192.8M-14.9%1.1M2.51
    15 February 20193.3M+9.3%1.1M3.01
    31 January 20193.0M+4.2%2.0M1.51
    15 January 20192.9M-2.4%1.6M1.79
    31 December 20182.9M+6.4%1.1M2.65
    14 December 20182.8M-0.5%1.1M2.41
    30 November 20182.8M-3.7%1.4M1.96
    15 November 20182.9M+28.2%1.5M1.90
    31 October 20182.3M+53.1%2.3M1.00
    15 October 20181.5M-11.9%1.2M1.22
    28 September 20181.7M-0.8%582K2.87
    14 September 20181.7M-2.9%636K2.65
    31 August 20181.7M-4.0%697K2.49
    15 August 20181.8M+3.8%628K2.87
    31 July 20181.7M-3.3%882K1.97
    13 July 20181.8M-6.8%695K2.59
    29 June 20181.9M-26.9%1.0M1.91
    15 June 20182.6M+0.9%938K2.82
    31 May 20182.6M+18.7%1.1M2.48
    15 May 20182.2M+7.7%984K2.24
    30 April 20182.0M+10.7%1.3M1.55
    13 April 20181.9M+8.0%772K2.40
    29 March 20181.7M-10.2%888K1.93
    15 March 20181.9M-14.8%871K2.19
    28 February 20182.2M+5.6%915K2.45
    15 February 20182.1M-16.8%1.5M1.40
    31 January 20182.6M-7.4%1.4M1.76
    12 January 20182.8M+13.2%1.2M2.34
    29 December 20172.4M827K2.94
    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.