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Puma Biotechnology, Inc. short interest

4.5M shares of Puma Biotechnology were sold short at the 15 October 2026 settlement, the most since 15 Apr 2021. Short sellers would need 12.9 days of normal trading to buy them back.

Shares sold short4.5Mat 15 Oct 2026
Change on the settlement before+6.5%+35% over a year
Days to cover12.88at 353K shares a day
Of shares in issue8.88%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 since 15 Apr 2021, and the share price moved +92% 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 20264.5M+6.5%353K12.88
    30 September 20264.3M-1.3%304K14.02
    15 September 20264.3M+1.1%313K13.80
    31 August 20264.3M+2.6%274K15.62
    14 August 20264.2M+1.0%366K11.39
    31 July 20264.1M+5.6%297K13.89
    15 July 20263.9M+7.7%367K10.65
    30 June 20263.6M-1.9%428K8.47
    15 June 20263.7M-2.7%201K18.41
    29 May 20263.8M-9.3%193K19.73
    15 May 20264.2M+2.2%356K11.79
    30 April 20264.1M-1.2%221K18.59
    15 April 20264.2M+5.6%330K12.60
    31 March 20263.9M-4.2%237K16.64
    13 March 20264.1M+9.2%467K8.79
    27 February 20263.8M+2.8%502K7.50
    13 February 20263.7M+5.2%430K8.52
    30 January 20263.5M-3.1%447K7.79
    15 January 20263.6M+4.3%363K9.89
    31 December 20253.4M+0.4%359K9.61
    15 December 20253.4M+0.6%402K8.53
    28 November 20253.4M+2.3%405K8.42
    14 November 20253.3M-0.3%919K3.63
    31 October 20253.3M-0.6%399K8.38
    15 October 20253.4M-4.5%475K7.07
    30 September 20253.5M+3.6%520K6.77
    15 September 20253.4M+22.7%541K6.28
    29 August 20252.8M+4.4%762K3.63
    15 August 20252.7M-4.8%1.1M2.44
    31 July 20252.8M+6.9%306K9.09
    15 July 20252.6M-1.1%341K7.65
    30 June 20252.6M-1.6%302K8.71
    13 June 20252.7M-3.9%467K5.73
    30 May 20252.8M-2.9%342K8.14
    15 May 20252.9M-2.2%387K7.42
    30 April 20252.9M+2.2%234K12.54
    15 April 20252.9M-0.5%349K8.22
    31 March 20252.9M+3.2%359K8.04
    14 March 20252.8M-11.5%473K5.91
    28 February 20253.2M+2.9%553K5.71
    14 February 20253.1M+2.8%249K12.34
    31 January 20253.0M-3.0%402K7.43
    15 January 20253.1M+2.2%1.1M2.78
    31 December 20243.0M+3.5%543K5.55
    13 December 20242.9M+3.6%478K6.08
    29 November 20242.8M-6.0%390K7.20
    15 November 20243.0M-6.4%772K3.86
    31 October 20243.2M-11.8%194K16.42
    15 October 20243.6M+6.0%233K15.49
    30 September 20243.4M-5.7%302K11.30
    13 September 20243.6M+4.0%283K12.79
    30 August 20243.5M-13.1%380K9.14
    15 August 20244.0M+4.7%458K8.73
    31 July 20243.8M+0.6%334K11.45
    15 July 20243.8M+29.7%413K9.19
    28 June 20242.9M+8.6%1.0M2.82
    14 June 20242.7M+7.3%276K9.77
    31 May 20242.5M-17.4%503K4.99
    15 May 20243.0M-2.3%347K8.77
    30 April 20243.1M-6.4%257K12.10
    15 April 20243.3M+1.0%351K9.49
    28 March 20243.3M-1.2%766K4.30
    15 March 20243.3M-18.5%654K5.10
    29 February 20244.1M+14.0%800K5.11
    15 February 20243.6M+11.9%693K5.18
    31 January 20243.2M+6.3%427K7.50
    12 January 20243.0M+4.2%397K7.60
    29 December 20232.9M+4.8%262K11.06
    15 December 20232.8M+35.5%272K10.17
    30 November 20232.0M+8.4%308K6.61
    15 November 20231.9M+9.3%344K5.47
    31 October 20231.7M-1.0%91K18.92
    13 October 20231.7M-0.5%110K15.76
    29 September 20231.7M+1.0%122K14.36
    15 September 20231.7M+3.3%128K13.55
    31 August 20231.7M+2.6%133K12.63
    15 August 20231.6M+0.7%189K8.65
    31 July 20231.6M-2.6%130K12.47
    14 July 20231.7M+3.9%243K6.85
    30 June 20231.6M+11.5%239K6.69
    15 June 20231.4M+5.3%228K6.30
    31 May 20231.4M+0.4%241K5.66
    15 May 20231.4M-1.6%220K6.17
    28 April 20231.4M+7.0%173K7.98
    14 April 20231.3M-0.4%242K5.32
    31 March 20231.3M+8.4%446K2.90
    15 March 20231.2M+4.1%479K2.49
    28 February 20231.1M+2.5%211K5.45
    15 February 20231.1M+6.6%282K3.97
    31 January 20231.1M+12.2%234K4.49
    13 January 2023936K+6.3%431K2.17
    30 December 2022881K-38.1%433K2.03
    15 December 20221.4M-5.5%488K2.91
    30 November 20221.5M+0.7%537K2.80
    15 November 20221.5M-1.9%344K4.34
    31 October 20221.5M-0.1%113K13.47
    14 October 20221.5M-4.4%107K14.22
    30 September 20221.6M-9.7%159K10.02
    15 September 20221.8M-2.3%209K8.45
    31 August 20221.8M-1.3%177K10.19
    15 August 20221.8M+2.4%329K5.56
    29 July 20221.8M-3.7%178K10.03
    15 July 20221.9M-7.4%308K6.02
    30 June 20222.0M-41.9%846K2.37
    15 June 20223.5M-1.0%513K6.73
    31 May 20223.5M+4.8%337K10.35
    13 May 20223.3M+4.6%516K6.45
    29 April 20223.2M+3.0%304K10.46
    14 April 20223.1M-1.5%364K8.48
    31 March 20223.1M+10.4%508K6.17
    15 March 20222.8M+21.4%631K4.50
    28 February 20222.3M+1.8%287K8.16
    15 February 20222.3M-6.4%339K6.79
    31 January 20222.5M-4.2%689K3.57
    14 January 20222.6M-13.5%868K2.95
    31 December 20213.0M+6.4%458K6.48
    15 December 20212.8M-10.0%876K3.18
    30 November 20213.1M+22.3%769K4.03
    15 November 20212.5M+4.1%1.2M2.07
    29 October 20212.4M-2.7%450K5.41
    15 October 20212.5M-7.6%459K5.45
    30 September 20212.7M-5.2%434K6.25
    15 September 20212.9M-0.5%280K10.20
    31 August 20212.9M-2.4%328K8.75
    13 August 20212.9M-4.3%725K4.06
    30 July 20213.1M+6.5%226K13.63
    15 July 20212.9M+7.2%379K7.62
    30 June 20212.7M-28.4%597K4.52
    15 June 20213.8M-2.4%296K12.72
    28 May 20213.9M-6.1%198K19.46
    14 May 20214.1M-0.3%290K14.18
    30 April 20214.1M-10.3%209K19.76
    15 April 20214.6M-5.8%300K15.31
    31 March 20214.9M-0.1%284K17.18
    15 March 20214.9M+0.2%307K15.95
    26 February 20214.9M+3.7%292K16.69
    12 February 20214.7M-4.4%393K11.96
    29 January 20214.9M+0.9%482K10.20
    15 January 20214.9M-26.9%335K14.56
    31 December 20206.7M-14.5%500K13.35
    15 December 20207.8M+0.8%745K10.48
    30 November 20207.7M-4.1%477K16.25
    13 November 20208.1M+1.0%550K14.68
    30 October 20208.0M+2.2%422K18.96
    15 October 20207.8M+7.7%507K15.43
    30 September 20207.3M-1.6%581K12.51
    15 September 20207.4M-0.9%586K12.60
    31 August 20207.4M+1.4%522K14.27
    14 August 20207.3M+3.9%1.2M6.07
    31 July 20207.1M+2.3%576K12.27
    15 July 20206.9M+1.3%875K7.89
    30 June 20206.8M-7.6%1.2M5.70
    15 June 20207.4M-0.8%897K8.23
    29 May 20207.4M-5.6%780K9.54
    15 May 20207.9M+0.1%1.4M5.69
    30 April 20207.9M-6.7%772K10.19
    15 April 20208.4M-1.3%983K8.59
    31 March 20208.5M+17.0%1.4M6.31
    13 March 20207.3M+3.2%1.2M6.05
    28 February 20207.1M-3.6%2.1M3.41
    14 February 20207.3M-7.7%4.1M1.79
    31 January 20208.0M+1.6%1.6M5.05
    15 January 20207.8M+12.4%1.4M5.57
    31 December 20197.0M-1.7%1.5M4.57
    13 December 20197.1M+3.9%2.3M3.03
    29 November 20196.8M+2.9%1.4M5.05
    15 November 20196.6M-14.1%1.9M3.56
    31 October 20197.7M-5.9%1.4M5.68
    15 October 20198.2M+0.3%1.8M4.51
    30 September 20198.2M-8.6%1.6M4.99
    13 September 20198.9M+1.0%1.5M5.91
    30 August 20198.8M-0.1%1.1M8.30
    15 August 20198.9M+20.6%2.1M4.20
    31 July 20197.3M-2.7%1.3M5.67
    15 July 20197.5M+10.3%992K7.60
    28 June 20196.8M+73.9%1.8M3.90
    14 June 20193.9M-9.4%991K3.97
    31 May 20194.3M+4.7%910K4.77
    15 May 20194.1M-4.6%2.0M2.11
    30 April 20194.3M-8.4%619K7.02
    15 April 20194.7M+26.3%781K6.07
    29 March 20193.8M-21.5%711K5.28
    15 March 20194.8M+3.0%2.2M2.13
    28 February 20194.6M-6.3%1.1M4.40
    15 February 20195.0M-4.8%570K8.69
    31 January 20195.2M+15.9%900K5.79
    15 January 20194.5M+8.2%1.1M4.23
    31 December 20184.2M+17.3%1.3M3.12
    14 December 20183.5M-8.7%996K3.55
    30 November 20183.9M+2.0%782K4.96
    15 November 20183.8M-19.2%3.8M1.01
    31 October 20184.7M-7.2%767K6.14
    15 October 20185.1M+9.6%668K7.60
    28 September 20184.6M+14.9%663K6.98
    14 September 20184.0M+10.8%894K4.50
    31 August 20183.6M-16.3%639K5.69
    15 August 20184.3M-5.6%1.2M3.57
    31 July 20184.6M-4.3%596K7.72
    13 July 20184.8M+5.8%617K7.79
    29 June 20184.5M+64.8%1.7M2.70
    15 June 20182.8M+1.4%904K3.05
    31 May 20182.7M-9.3%569K4.78
    15 May 20183.0M-3.4%1.2M2.59
    30 April 20183.1M-0.4%486K6.38
    13 April 20183.1M-4.8%665K4.68
    29 March 20183.3M+1.0%611K5.35
    15 March 20183.2M-6.9%1.2M2.65
    28 February 20183.5M-3.8%646K5.38
    15 February 20183.6M+5.5%956K3.78
    31 January 20183.4M+24.9%1.7M1.97
    12 January 20182.7M+2.9%599K4.58
    29 December 20172.7M568K4.70
    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.