aTyr Pharma, Inc. (ATYR) short interest & short volume · 11.8% of float short
aTyr Pharma, Inc. official short interest (FINRA, twice monthly) and daily short volume (FINRA Reg SHO), with history, % of float and days to cover.
What changed
ATYR short interest fell 20.3% to 10.3M shares in the Oct 15, 2026 report (11.8% of float, 5.4 days to cover). Daily short volume averaged 47.0% of volume over the last 20 sessions, down from 53.4% the 20 sessions before, the 45th percentile of its own 20-day averages since Sep 22, 2025.
Short interest
Official, twice monthly · settled Oct 15, 2026
- Shares short
- 10.3M
- prior 12.9M
- % of float
- 11.8%
- float 87.0M
- Days to cover
- 5.4
- avg vol 1.9M
- Change vs prior report
- -20.3%
Days to cover is short interest divided by FINRA's average daily volume for the period: how many average days of trading it would take shorts to buy back.
% of float uses the current float for every report (no float was stored with older reports).
Source: FINRA equity short interest (twice monthly) · Settlement Oct 15, 2026
Daily short volume
Share of each day's volume sold short · FINRA Reg SHO
- Latest (Nov 2)
- 58.1%
- 129K of 222K
- 20-day average
- 47.0%
- prior 53.4%
- Percentile vs own history
- 45th
- 233 periods since 2025
Loading prices…
Source: FINRA Reg SHO daily short sale volume · Latest Nov 2, 2026
Short squeeze score (model)
Price since settlement: +3507.2%
Model, not a forecast: 40 pts short interest % of float (full at 30%), 25 pts days to cover (full at 10), 15 pts rise in short interest since the prior report (full at +50%), 20 pts price gain since the settlement date (full at +25%). Missing inputs score 0.
ATYR's squeeze score and its inputs with Lician Pro.Start 3-day trial — $149/yr
Market-wide: most shorted stocks, biggest changes and unusual short volume · ATYR overview
| Date | Short | Total | Short % of volume |
|---|---|---|---|
| 2026-11-02 | 128,912 | 221,948 | 58.1% |
| 2026-10-30 | 40,119 | 76,439 | 52.5% |
| 2026-10-29 | 77,257 | 151,341 | 51.0% |
| 2026-10-28 | 1,156,774 | 1,876,065 | 61.7% |
| 2026-10-27 | 3,223,415 | 4,839,947 | 66.6% |
| 2026-10-26 | 1,065,205 | 1,884,721 | 56.5% |
| 2026-10-23 | 301,534 | 818,224 | 36.9% |
| 2026-10-22 | 227,121 | 618,189 | 36.7% |
| 2026-10-21 | 217,528 | 549,939 | 39.5% |
| 2026-10-20 | 366,753 | 846,358 | 43.3% |
Healthcare peers with similar quant ratings
ATYR among 532 rated Healthcare stocks (Lician quant rating, Nov 4, 2026). How the rating works
- QTTB short interest5.00 · Strong Buy · stock
- AVAH short interest4.99 · Strong Buy · stock
- CDNA short interest4.98 · Strong Buy · stock
- HALO short interest4.97 · Strong Buy · stock
- OSCR short interest4.97 · Strong Buy · stock
- BTSG short interest4.96 · Strong Buy
- REGN short interest4.95 · Strong Buy · stock
- CON short interest4.94 · Strong Buy · stock
ATYR short interest FAQ
What is ATYR's short interest?
aTyr Pharma, Inc. (ATYR) had 10.3M shares sold short and not yet covered in FINRA's Oct 15, 2026 settlement report, 11.8% of its 87.0M-share float.
How many days to cover does ATYR have?
5.4 days: 10.3M shares short divided by an average daily volume of 1.9M for the Oct 15, 2026 period.
Is ATYR short interest rising or falling?
ATYR short interest fell (-20.3%) from 12.9M to 10.3M shares in the Oct 15, 2026 report.
Is ATYR a short squeeze candidate?
Lician's squeeze watch scores ATYR 49 out of 100 (elevated) from the Oct 15, 2026 report: short interest % of float 15.7/40, days to cover 13.5/25, change in short interest vs prior report 0/15, price change since settlement date 20/20. It is a transparent model of how crowded the short side is, not a forecast that a squeeze will happen.
What share of ATYR daily volume is sold short?
47.0% on average over the last 20 sessions to Nov 2, 2026 (FINRA Reg SHO daily short volume; the 45th percentile of its own 20-day averages). Short volume counts market makers' same-day short sales, so it is not short interest.
What was ATYR's latest FINRA short volume?
On Nov 2, 2026, cached FINRA short volume for aTyr Pharma, Inc. (ATYR) was 128,912 shares, 58.1% of 221,948 total volume.
How many ATYR short-volume sessions are listed on this page?
This page lists 10 cached FINRA short-volume sessions for aTyr Pharma, Inc. (ATYR), from Oct 20, 2026 through Nov 2, 2026.
How did ATYR short volume percent change from the prior cached session?
Cached FINRA short volume for aTyr Pharma, Inc. (ATYR) moved from 52.5% on Oct 30, 2026 to 58.1% on Nov 2, 2026, up 5.6 percentage points.
Not investment advice. Figures as filed or reported, not a live feed.