When this was written — On 21 October 2026. The figures are as at that date or earlier and have not been updated since.
Artrya was 9.59% shorted on 15 October in ASIC's daily aggregate report: 15,696,909 of 163,633,618 shares on issue. R1 On 16 July it was 0.93%, or 1,517,487 shares. R2 The share count rose by 0.7 million over the quarter; the position rose by 14.2 million shares, a little over ten times.
Almost all of it is four weeks old. On 17 September the position was 1.78%, where it had sat, give or take half a point, since April. R3 On 18 September it was 4.73%, 7,729,821 shares. R4 That one-day step of 2.95 percentage points added 4.83 million shares, more than the entire position of the day before. It kept building on most sessions after that: 6.32% on 22 September, 7.63% on 29 September, 8.96% on 6 October, and a peak of 10.17% on 14 October, 16,645,366 shares. R5 The 15 October print was the first meaningful retreat, a 0.58 percentage point fall.
On the screener that is the largest four-week change on the ASX for any stock with a market capitalisation above $300 million, at +7.82 percentage points. The next largest, Boss Energy, is +4.59.
The session the position rose about 2.7 times
18 September was also the stock's heaviest day. Artrya traded 14,738,256 shares, about 9% of the company, and closed at $3.94, up 8.2% on the day after an 11% rise on 17 September. In the daily record from 14 September to 20 October no other session reached 3.5 million shares. The short step and the volume spike are the same date in the data, which says nothing about who was on which side: an aggregate position cannot separate a directional short from a hedge against stock that changed hands that day.
Then the price turned. The close was $3.81 on 25 September, $3.25 on 5 October, $3.01 on 9 October and $2.59 on 15 October, a 10.1% fall on the day. It was $2.54 at the 20 October close, 35.5% below the 18 September close and 52.1% below the $5.30 of 21 July. Days to cover are 7.4 on the 20-day average volume.
What the company lodged
The announcements in the window are register notices and one contract. On 17 September, the day before the step, Wilson Asset Management's WAM, WAA, WMI and WAX funds ceased to be a substantial holder. 8 New substantial holders were notified on 23 September 9 and 28 September, 10 and a holder ceased on 29 September. 11 None of those notices says anything about short positions; ASIC's report is the only disclosure of those, and it names no one.
On 1 October Artrya announced a commercial agreement with Huntsville Hospital Health System in the United States. 7 The shares closed $3.70 on 2 October, up 7.9%, with 3.46 million traded, then $3.25 on 5 October. The notice of annual general meeting was lodged on 13 October. 12
Shorted's parsed extraction of the company's Appendix 4E, lodged on 19 August, records revenue of $28,000 and a net loss of $25.18 million, against a $16.41 million loss the year before, with no dividend. The same extraction describes a business moving to commercial stage, with its first US customers and FDA clearance for the Salix Coronary Plaque module. R6 A company at that stage is valued on what its software will earn, so a short position of this size is a view on that, on the funding needed to get there, or a hedge. The report does not say which.
Where it sits
Among health care equipment and services names, only 4DMedical at 10.65% is more shorted; PolyNovo is 7.35% and Nanosonics 6.98%. Artrya was not in the sector's top ten a quarter ago. On Shorted's crowded-short breakout screen it reads as a setup, 56th of 1,310 evaluated: the position is crowded, the price is well under its pivot, and the market regime rule fails with the ASX 200 below its 200-day average.
ASIC publishes the aggregate four trading days after the position date, so the 15 October figure is the latest available on 21 October. The chart is live; the figures above are pinned to their dates, and the AYA page will show whether the 15 October fall was the start of covering or a pause.
Disclosure analysis, not a recommendation to buy or sell.