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ACIU
AC Immune SA
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ACIU in the last 90 days
AC Immune SA (ACIU) had no US House transactions and no insider purchases in filings from the last 90 days.
FINRA’s latest report (settlement 15 SEPT 2026) shows 3,475,472 shares held short, 25.0 days to cover, up 5.4% from the report before.
- Delay: each filing below shows how many days passed between the trade and its publication. None of this is real-time.
Latest filing on file: — · FINRA settlement 15 SEPT 2026 · public filings, reported as filed
What the filings show
What the filings show · last 90 days · Quiet Money indicator
1 of 4 sources
-6Balanced
The disclosed money is split, on what has actually been filed. This reads on one source only, so treat it lightly.
- Short interest
- Short interest rose 2.3% — 3,395,949 to 3,475,472 shares between 15 JUL 2026 and 15 SEPT 2026. See the filings →
- -6
This summarises filings that have already been published — it is not a forecast, a rating of the company, or advice. Every figure above is listed in full further down this page, with the document it came from.
FINRA short interest
Settlement 15 SEPT 2026 · shares held short
3,475,472shares held short
Days to cover
25.00
Avg daily volume
139,040
Since last report
+5.44%
As of 15 September 2026, 3,475,472 AC Immune SA shares were held short — the total across every reporting firm, not one fund's position. That is 179,341 shares more than the previous report, a 5.44% increase. At the average daily volume of 139,040 shares, that position represents 25.00 days of trading — what the filing calls days to cover.
This is the most recent figure that exists, and it is 21 days old. FINRA collects short interest twice a month, on a settlement date, and publishes it seven business days later. So nobody has a live short-interest number for ACIU — not us, and not anyone quoting one. We print the settlement date on the figure so you always know which day you are looking at.
Across the 12 reports we hold, the position has risen from 2,964,467 shares on 31 March 2026 to 3,475,472 today, a change of 17.2%. The highest reading in that window was 3,551,322 shares on 31 July 2026.
| Settlement | Shares short | Days to cover |
|---|---|---|
| 15 SEPT 2026 | 3,475,472 | 25.00 |
| 31 AUG 2026 | 3,296,131 | 14.99 |
| 14 AUG 2026 | 3,405,907 | 14.29 |
| 31 JUL 2026 | 3,551,322 | 18.18 |
| 15 JUL 2026 | 3,395,949 | 13.27 |
| 30 JUN 2026 | 3,376,932 | 12.99 |
| 15 JUN 2026 | 3,516,192 | 9.60 |
| 29 MAY 2026 | 3,353,471 | 16.31 |
| 15 MAY 2026 | 3,226,453 | 10.12 |
| 30 APR 2026 | 3,034,113 | 12.91 |
| 15 APR 2026 | 2,933,523 | 10.01 |
| 31 MAR 2026 | 2,964,467 | 14.59 |
- What is ACIU's short interest?
- 3,475,472 shares, as of the 15 September 2026 settlement date. That is the figure FINRA published, unadjusted.
- What percentage of the float is short?
- We do not publish that, because FINRA does not publish float. The regulator reports the number of shares held short; turning it into a percentage needs a share count from somewhere else, and different sources disagree about what counts as float. We would rather give you the number that was actually filed than a percentage built on an assumption.
- How current is this?
- It is 21 days old, and that is as fresh as short interest gets. FINRA measures it twice a month and publishes it seven business days after the settlement date. Any site showing you a "live" short interest figure is showing you something else.
- What does days to cover mean?
- It is the short position divided by average daily trading volume — here, 25.00. It describes how many days of ordinary trading the position is equivalent to. It is arithmetic from the filing, not a prediction about what will happen.
- Where does this come from?
- FINRA's consolidated short interest file, which is public. We read it directly and store it unchanged, except that we blank the days-to-cover placeholder FINRA writes when a stock has almost no volume.
Disclosed insider buying on file
—no purchase on file passed the price check
Open-market purchases only — the amount is a fact, not a verdict.
On file here
Short positions0
Insider purchases0
US House transactions0
Latest change—