Two of the most heavily shorted companies on the ASX are about to report, days apart, and the positioning going in tells a more interesting story than either company's numbers will.
DroneShield carries 14.64% of its register short. 4DMedical carries 12.35%. Both peaked in late July — DroneShield at an all-time-high 16.03% on 31 July, 4DMedical at 13.40% on 23 July — and both have been unwinding since.
The reporting calendars matter here, and they are not the ones most people would guess.
What this data is, and when it is from — Short positions are ASIC's aggregated daily series, latest observation 18 August 2026. Filing dates come from ASX announcements. The expected reporting dates below are inferred from each company's filings last year, not from a confirmed date — treat them as a timetable, not a diary entry.
Two different year-ends, one week
DroneShield reports on a December year-end. Its FY2025 statutory filing — "Appendix 4E and Annual Report" — landed on 25 February 2026. Its half-year, "Half Yearly Report and Accounts", landed on 27 August 2025. On that timetable the 1H26 result is due about now.
4DMedical reports on a June year-end. Its "Appendix 4E - Preliminary Final Report" and "FY2025 Full year results" both landed on 29 August 2025, with the Annual Report following on 26 September. Its FY26 half-year, "Appendix 4D and FY26 Half Year Report", came on 27 February 2026. On that timetable the FY26 full-year result is also due about now.
So a December-year-end company filing its half-year and a June-year-end company filing its full-year arrive in the same window, both with near-record short interest.
The build, side by side
Month-end short interest, percentage of issued capital:
| Sep 25 | Nov 25 | Jan 26 | Mar 26 | May 26 | Jul 26 | 18 Aug | |
|---|---|---|---|---|---|---|---|
| DRO | 5.14% | 8.62% | 8.90% | 11.76% | 10.98% | 16.03% | 14.64% |
| 4DX | 0.00% | 0.03% | 0.02% | 2.33% | 10.06% | 13.13% | 12.35% |
DroneShield's build is the one that gets attention — it is the second-most-shorted stock on the ASX. But 4DMedical's is the stranger chart.
4DMedical sat at effectively zero for six straight months. From September 2025 through January 2026 the position ranged between 0.00% and 0.04%. It then went to 13.40% in five months. DroneShield's build took twelve months and started from a real base of 2.60%; 4DMedical's started from nothing.
A position going from zero to 10% in four months is not a view being expressed gradually. That is a thesis arriving.
The most useful thing in this data: DroneShield's bears sat through the last one
This is the part worth dwelling on, because it is a rare case where the data answers a question people usually only speculate about.
DroneShield filed its FY2025 Appendix 4E on 25 February 2026. Here is what the short position did around it:
| Date | Short % |
|---|---|
| 19 Feb | 9.84% |
| 23 Feb | 9.82% |
| 24 Feb (day before) | 9.90% |
| 25 Feb (filing) | 9.61% |
| 26 Feb (day after) | 9.29% |
| 27 Feb | 9.45% |
| 6 Mar | 8.95% |
The position fell by roughly 0.6 percentage points across the result and then stabilised. On a 9.9% position, that is a trim, not a capitulation — and by early March it was still near 9%.
Then it went to 16.03% by the end of July.
The bears held through a full-year result and subsequently increased the position by two thirds. Whatever the FY2025 numbers said, it did not break the thesis of the people positioned against it.
What each company has been doing lately
The announcement flow going into these results is very different.
4DMedical has been raising capital. In the last month: a Quarterly Activity Report and Appendix 4C on 31 July, two "proposed issue of securities" updates, two applications for quotation of securities, and a cleansing notice. An Appendix 4C is a quarterly cash-flow report — the document a company files when cash burn is the number that matters. A cash-consuming company issuing stock into a 13% short interest is the most legible bear case on this page.
DroneShield has been announcing product and contracts. A Material Contracts, Product Release and Trading Update on 28 July, the RfRecon flagship launch on 10 August, an investor presentation on 11 August, and repeated substantial-holder changes through the month. That is a company pushing news against the position rather than raising into it.
The turn, and why it is too early to call
Both positions came off their July highs:
- DroneShield: 16.03% (31 Jul) → 15.65% (10 Aug) → 14.98% (17 Aug) → 14.64% (18 Aug). Down almost every week — the first sustained reduction of the entire build.
- 4DMedical: 13.40% (23 Jul) → 12.35% (18 Aug).
It is tempting to read a pre-result unwind as bears losing conviction. The same data argues against that reading: DroneShield did exactly this in January, when a then-record 10.89% fell to 8.90%, and the build not only resumed but went 80% higher.
A 1.4-point reduction off a 16% position is what risk management looks like ahead of a binary event. It is not the same as an exit.
What the data cannot tell you
ASIC's aggregate contains no reasoning, and this matters more than usual for these two.
It does not separate a bear from a hedger. A convertible-note holder hedging exposure appears in the identical column to someone betting on a fall. For 4DMedical — actively issuing securities — that ambiguity is live rather than theoretical: some of that short interest may be hedging the very issuance it superficially looks like a bet against.
It does not predict the result. A large short position is a disclosure, not a forecast. It tells you a meaningful group of institutions is positioned one way and has been willing to hold through at least one reporting event.
And crowding cuts both ways. 14.64% of DroneShield is simultaneously the bear case's strongest expression and the largest pool of forced buyers that exists if the result breaks the thesis. That is the mechanics behind every short squeeze.
What to watch
- Whether either position moves more than ~1pp across the result. DroneShield's February benchmark is 0.6pp. A materially larger move is the informative outcome, in either direction.
- Whether DroneShield takes out 16.03%. That is the all-time high, set three weeks before the result.
- Whether 4DMedical's position survives at all. Unlike DroneShield, it has no track record of holding through a result — the entire position was built after the last one.
Follow both on DRO and 4DX, or see where they sit on the most-shorted board.
Short-position data from ASIC's aggregated short position reports, latest observation 18 August 2026. Filing dates from ASX announcements. This is a description of public positioning data, not investment advice.