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Atossa Therapeutics (ATOS) Stock: Why It's Down Today
Updated Oct 20, 2026, 4:00 PM ET · closing price
At a glance
- Latest (Nasdaq last sale, Oct 21, 7:50 AM ET): $2.54, −$0.02 (-0.78%).
- Earnings: latest quarter in SEC XBRL filings (ended Jun 30, 2026): diluted EPS $-0.95; next earnings Wed Nov 11. Sources: SEC EDGAR XBRL, Nasdaq earnings calendar.
Sector peers moving today (Pharma & Biotech):MYGN +31.59%EVAX +21.62%IRLA +16.89%QNCX +16.89%LRMR +15.09%
What changed since yesterday
- Closed at $2.54, -0.78% vs the prior close of $2.56.
- Volume 21.30K shares, 0.3x its 50-day average (light).
- No new SEC filings since the prior session.
- No new insider buys or sales reported since the prior session.
Compare with peers today
Eli Lilly (LLY)Johnson & Johnson (JNJ)AbbVie (ABBV)Merck (MRK)Abbott Laboratories (ABT)Pfizer (PFE)
ATOS dips 0.8% to $2.54. Closed at $2.54, -0.78% vs the prior close of $2.56. Day range $2.51–$2.67, opened at $2.54.
Last close$2.54-0.78%
Day range2.51–2.67
Open2.54
Volume21.30K
52-week range1.70–15.30
Avg volume (20d)97.83K
ATOS daily analysis — what happened
A plain-English, data-only note for every US trading day (today's note updates every 2 hours while the market is open). Newest first; older days stay archived below.
Oct 20, 2026 — ATOS dips 0.8% to $2.54
- Closed at $2.54, -0.78% vs the prior close of $2.56. Day range $2.51–$2.67, opened at $2.54.
- Volume was 21.30K shares, 0.3x its 50-day average of 74.51K — lighter than usual.
- Price is +4.0% vs its 50-day average ($2.44) and -40.0% vs its 200-day average ($4.24).
- 52-week range $1.70–$15.30; today's close sits at 6% of that range, 83.4% below the 52-week high.
Oct 19, 2026 — ATOS slides 12.0% to $2.56
- Closed at $2.56, -12.03% vs the prior close of $2.91. Day range $2.53–$2.76, opened at $2.66.
- Volume was 80.14K shares, 1.1x its 50-day average of 74.47K.
- Price is +5.0% vs its 50-day average ($2.44) and -40.0% vs its 200-day average ($4.27).
- 52-week range $1.70–$15.45; today's close sits at 6% of that range, 83.4% below the 52-week high.
Oct 16, 2026 — ATOS jumps 9.8% to $2.91, a 3-month high
- Closed at $2.91, +9.81% vs the prior close of $2.65. Day range $2.51–$2.95, opened at $2.59.
- Volume was 103.12K shares, 1.4x its 50-day average of 73.00K.
- Price is +19.6% vs its 50-day average ($2.43) and -32.3% vs its 200-day average ($4.30).
- 52-week range $1.70–$16.50; today's close sits at 8% of that range, 82.4% below the 52-week high.
Oct 15, 2026 — ATOS slides 4.7% to $2.65 on 3.3x normal volume
- Closed at $2.65, -4.68% vs the prior close of $2.78. Day range $2.53–$3.12, opened at $2.78.
- Volume was 226.20K shares, 3.3x its 50-day average of 69.21K — unusually heavy trading.
- Price is +9.3% vs its 50-day average ($2.42) and -38.8% vs its 200-day average ($4.33).
- 52-week range $1.70–$16.50; today's close sits at 6% of that range, 83.9% below the 52-week high.
Oct 14, 2026 — ATOS jumps 8.6% to $2.78, a 1-month high on 3.6x normal volume
- Closed at $2.78, +8.59% vs the prior close of $2.56. Day range $2.45–$2.81, opened at $2.52.
- Volume was 236.10K shares, 3.6x its 50-day average of 65.59K — unusually heavy trading.
- Price is +14.9% vs its 50-day average ($2.42) and -36.4% vs its 200-day average ($4.37).
- 52-week range $1.70–$16.50; today's close sits at 7% of that range, 83.2% below the 52-week high.
Oct 13, 2026 — ATOS jumps 7.1% to $2.56, a 1-month high
- Closed at $2.56, +7.11% vs the prior close of $2.39. Day range $2.30–$2.60, opened at $2.35.
- Volume was 70.70K shares, 1.1x its 50-day average of 64.66K.
- Price is +6.3% vs its 50-day average ($2.41) and -41.9% vs its 200-day average ($4.41).
- 52-week range $1.70–$17.25; today's close sits at 6% of that range, 85.2% below the 52-week high.
Oct 12, 2026 — ATOS dips 2.0% to $2.39
- Closed at $2.39, -2.05% vs the prior close of $2.44. Day range $2.34–$2.53, opened at $2.44.
- Volume was 81.40K shares, 1.3x its 50-day average of 64.61K.
- Price is -0.5% vs its 50-day average ($2.40) and -46.2% vs its 200-day average ($4.44).
- 52-week range $1.70–$18.00; today's close sits at 4% of that range, 86.7% below the 52-week high.
Oct 9, 2026 — ATOS rises 0.8% to $2.44 on 4.4x normal volume
- Closed at $2.44, +0.83% vs the prior close of $2.42. Day range $2.12–$2.74, opened at $2.45.
- Volume was 265.60K shares, 4.4x its 50-day average of 59.94K — unusually heavy trading.
- Price is +1.9% vs its 50-day average ($2.40) and -45.6% vs its 200-day average ($4.48).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.4% below the 52-week high.
- SEC filings that day: 8-K.
Oct 8, 2026 — ATOS dips 1.6% to $2.42
- Closed at $2.42, -1.63% vs the prior close of $2.46. Day range $2.39–$2.48, opened at $2.46.
- Volume was 100.80K shares, 1.7x its 50-day average of 58.74K.
- Price is +1.2% vs its 50-day average ($2.39) and -46.5% vs its 200-day average ($4.52).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.5% below the 52-week high.
Oct 7, 2026 — ATOS rises 0.4% to $2.46
- Closed at $2.46, +0.41% vs the prior close of $2.45. Day range $2.41–$2.49, opened at $2.41.
- Volume was 19.10K shares, 0.3x its 50-day average of 59.27K — lighter than usual.
- Price is +3.0% vs its 50-day average ($2.39) and -46.1% vs its 200-day average ($4.57).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.3% below the 52-week high.
Oct 6, 2026 — ATOS ends flat (+0.0%) to $2.45
- Closed at $2.45, +0.00% vs the prior close of $2.45. Day range $2.43–$2.54, opened at $2.46.
- Volume was 54.60K shares, 0.9x its 50-day average of 58.92K.
- Price is +2.6% vs its 50-day average ($2.39) and -46.8% vs its 200-day average ($4.61).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.3% below the 52-week high.
Oct 5, 2026 — ATOS jumps 4.7% to $2.45, 3 up days in a row
- Closed at $2.45, +4.70% vs the prior close of $2.34. Day range $2.34–$2.50, opened at $2.38.
- Volume was 53.30K shares, 0.9x its 50-day average of 58.66K.
- Price is +2.7% vs its 50-day average ($2.39) and -47.3% vs its 200-day average ($4.65).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.3% below the 52-week high.
- That makes 3 straight gains.
Oct 2, 2026 — ATOS jumps 3.1% to $2.34
- Closed at $2.34, +3.08% vs the prior close of $2.27. Day range $2.17–$2.38, opened at $2.23.
- Volume was 74.30K shares, 1.3x its 50-day average of 57.92K.
- Price is -1.8% vs its 50-day average ($2.38) and -50.1% vs its 200-day average ($4.69).
- 52-week range $1.70–$19.35; today's close sits at 4% of that range, 87.9% below the 52-week high.
ATOS bull case vs bear case (from the data)
Bull case
- Price is +4.0% vs its 50-day average — short-term trend is up.
- Share count down 92.3% in a year (buybacks).
Bear case
- Price is -40.0% vs its 200-day average — below the long-term trend line.
- Annual revenue fell 95.6% in the latest fiscal year (SEC XBRL).
- Latest fiscal-year net income: loss of $34.77M.
- High volatility: average daily move of 4.8% over 20 sessions.
- Thin trading (under $2M a day on average) can mean wide bid/ask spreads.
ATOS latest news & SEC filings
Every SEC filing by or about ATOS in the last 120 days, explained in plain English. Updated daily, with a same-day refresh for new filings.
Oct 9, 2026 · Form 8-K — Major event / current report
Current report — a filing companies must make within 4 business days of a major event
- Item 1.01 — Signed a material agreement.
- Item 3.03 — Change to shareholder rights.
- Item 8.01 — Reported other events the company considers important.
Sep 29, 2026 · Form 8-K — Major event / current report
Current report — a filing companies must make within 4 business days of a major event
- Item 8.01 — Reported other events the company considers important.
Sep 18, 2026 · Form 8-K — Major event / current report
Current report — a filing companies must make within 4 business days of a major event
- Item 7.01 — Released information under Regulation FD (e.g. a presentation or press release).
Aug 7, 2026 · Form 8-K — Major event / current report
Current report — a filing companies must make within 4 business days of a major event
- Item 2.02 — Reported results of operations (earnings release).
This is a results-day filing: the earnings press release is attached as an exhibit.
Aug 7, 2026 · Form 10-Q — Quarterly report
Quarterly report (unaudited financial statements for the quarter)
Quarter ended Jun 30, 2026:
- Net income: -$8.49M (prior year -$8.42M) (loss widened vs Jun 30, 2025)
- Diluted EPS: -$0.95 (prior year -$0.98) (loss narrowed vs Jun 30, 2025)
Things to know before you trade ATOS
- Last results release: Aug 7, 2026 (8-K Item 2.02). Previous ones: Jan 9, 2026, Nov 12, 2025, Aug 12, 2025. Based on that rhythm, the next report is likely around Nov 6, 2026 — an estimate, not a confirmed date.
- How much it moves: over the last 20 sessions the average daily move was 4.78% (largest 16.4%). That is a volatile stock.
- Liquidity: about 97.83K shares (≈$248.50K) trade per day on average. Thin volume can mean wider bid/ask spreads.
- 52-week position: $2.54 vs a range of $1.70–$15.30 (6% of the range).
- Dividends: no cash dividends in the last 2 years.
- Splits: 1:15 on Feb 2, 2026
- Insider trades (Form 4, last 12 months, recent 25 shown): 0 open-market buys, 0 sales.
- Latest filings: 8-K Oct 9, 2026; 8-K Sep 29, 2026; 8-K Sep 18, 2026.
- Share count: 9.98M shares outstanding (Jul 31, 2026), -92.3% vs a year earlier — the company has been reducing its share count.
- Listing: Nasdaq · industry: Pharmaceutical Preparations.
ATOS market data (last 20 sessions)
| Date | Open | High | Low | Close | Volume |
|---|---|---|---|---|---|
| Oct 20, 2026 | 2.54 | 2.67 | 2.51 | 2.54 | 21.30K |
| Oct 19, 2026 | 2.66 | 2.76 | 2.51 | 2.56 | 80.10K |
| Oct 16, 2026 | 2.59 | 2.95 | 2.51 | 2.91 | 104.20K |
| Oct 15, 2026 | 2.78 | 3.12 | 2.53 | 2.65 | 226.20K |
| Oct 14, 2026 | 2.52 | 2.81 | 2.45 | 2.78 | 236.10K |
| Oct 13, 2026 | 2.35 | 2.60 | 2.30 | 2.56 | 70.70K |
| Oct 12, 2026 | 2.44 | 2.53 | 2.34 | 2.39 | 81.40K |
| Oct 9, 2026 | 2.45 | 2.74 | 2.12 | 2.44 | 265.60K |
| Oct 8, 2026 | 2.46 | 2.48 | 2.39 | 2.42 | 100.80K |
| Oct 7, 2026 | 2.41 | 2.49 | 2.41 | 2.46 | 19.10K |
| Oct 6, 2026 | 2.46 | 2.54 | 2.43 | 2.45 | 54.60K |
| Oct 5, 2026 | 2.38 | 2.50 | 2.34 | 2.45 | 53.30K |
| Oct 2, 2026 | 2.23 | 2.38 | 2.17 | 2.34 | 74.30K |
| Oct 1, 2026 | 1.96 | 2.30 | 1.96 | 2.27 | 113.00K |
| Sep 30, 2026 | 1.99 | 2.15 | 1.95 | 1.95 | 67.80K |
| Sep 29, 2026 | 2.06 | 2.16 | 1.96 | 1.99 | 83.30K |
| Sep 28, 2026 | 1.91 | 2.04 | 1.82 | 1.96 | 152.90K |
| Sep 25, 2026 | 2.06 | 2.07 | 1.89 | 1.90 | 77.60K |
| Sep 24, 2026 | 2.15 | 2.22 | 2.05 | 2.05 | 37.20K |
| Sep 23, 2026 | 2.25 | 2.26 | 2.15 | 2.18 | 37.20K |
About Atossa Therapeutics
Atossa Therapeutics (ATOS) is listed on the Nasdaq and classified by the SEC under “Pharmaceutical Preparations”. Its business address is in SEATTLE, WA. State of incorporation: DE. Fiscal year ends December 31. SEC CIK 1488039.
ATOS board of directors & executives
From SEC Form 3/4/5 insider filings made in the last 12 months (date = latest filing).
Directors
| Name | Role | Latest filing |
|---|---|---|
| Shu-Chih Chen | Director | May 14, 2026 |
| Tessa Cigler | Director | May 14, 2026 |
| Jonathan Finn | Director | May 14, 2026 |
| Stephen J Galli | Director | May 14, 2026 |
| Steven C Quay | President & CEO | Mar 31, 2026 |
| H. Lawrence Remmel | Director | May 14, 2026 |
| Richard I Steinhart | Director | May 14, 2026 |
Executive officers
| Name | Title | Latest filing |
|---|---|---|
| Mark James Daniel | Chief Financial Officer | Mar 30, 2026 |
| Steven C Quay | President & CEO | Mar 31, 2026 |
Recent insider buys & sales
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| No open-market insider buys or sales reported in the last 12 months. | ||||
ATOS financials (annual, from XBRL filings)
| Fiscal year end | Revenue | Net income | Diluted EPS | Operating cash flow |
|---|---|---|---|---|
| Dec 31, 2025 | — | $-34.77M | -4.04 | $-29.76M |
| Dec 31, 2024 | — | $-25.50M | -3.04 | $-21.03M |
| Dec 31, 2023 | — | $-30.09M | -0.24 | $-20.94M |
| Dec 31, 2022 | — | $-26.96M | -0.21 | $-20.76M |
| Dec 31, 2021 | — | $-20.61M | — | $-16.47M |
Latest balance sheet: total assets $32.28M, total liabilities $5.45M, cash $26.09M (as of Jun 30, 2026).
ATOS earnings / results-day log
| Date | Filing | Close that day |
|---|---|---|
| Aug 7, 2026 | 8-K Item 2.02 (results) | $2.36 |
| Jan 9, 2026 | 8-K Item 2.02 (results) | $9.75 |
| Nov 12, 2025 | 8-K Item 2.02 (results) | $12.15 |
| Aug 12, 2025 | 8-K Item 2.02 (results) | $11.55 |
| May 13, 2025 | 8-K Item 2.02 (results) | $13.35 |
| Mar 25, 2025 | 8-K Item 2.02 (results) | $10.80 |
| Nov 12, 2024 | 8-K Item 2.02 (results) | $22.50 |
| Aug 12, 2024 | 8-K Item 2.02 (results) | — |
| May 13, 2024 | 8-K Item 2.02 (results) | — |
| Apr 1, 2024 | 8-K Item 2.02 (results) | — |
| Nov 13, 2023 | 8-K Item 2.02 (results) | — |
| Aug 14, 2023 | 8-K Item 2.02 (results) | — |
Related stocks · Pharmaceutical Preparations
Eli Lilly (LLY)Johnson & Johnson (JNJ)AbbVie (ABBV)Merck (MRK)Abbott Laboratories (ABT)Pfizer (PFE)Bristol Myers Squibb (BMY)Vertex Pharmaceuticals Inc / Ma (VRTX)Regeneron Pharmaceuticals (REGN)United Therapeutics (UTHR)
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Information only, not investment advice. BuyMeWhiskey is not a registered investment adviser or broker-dealer; nothing here is a recommendation to buy, sell or hold any security, and there are no price targets. Data comes from SEC EDGAR filings and public end-of-day market data and may be delayed or contain errors. Verify with the company's filings before making decisions. Prices: end-of-day data as of Oct 20, 2026, 4:00 PM ET. Filings: SEC EDGAR. Refreshed every 2 hours during US market hours.