QSI · Quantum-Si
Conviction · Low · more likely to lag the S&P 500 over the next three months
Wrong if: a daily close above $1.49
Note written ·
Price against the kill line
22.8% clear of its kill line on the 13 November 2026 close.
How to read this
This note expects the shares to lag the market, so its kill line sits above the price: a close above the red mark would prove the view wrong. Prices run from low on the left to high on the right. The dot is where the stock closed on 13 November 2026, left of the mark while it is below the line; a dot right of the mark has closed through it.
The scale is stretched near the line, so close calls are easy to see. More than 8% from the line, the stock reads well clear, with a hollow dot to show the figure is off the drawn scale.
The kill line is the research note's own test. The portfolio sells on business facts, not on a price. How the portfolio decides
Three months against the kill line
Daily closes, to . Red: the kill line, a daily close above $1.49, on record since 11 November 2026. The shares are up 54.5% since the close; the S&P 500 is down 2.1% over the same sessions. Figures in the note can cover a different window.
Kill line
A daily close above $1.49, over the 9 November 2026 close of $1.37, which would show the shares leading the S&P 500 again. A result pointing the same way: detection of all 20 amino acids announced before 31 December 2026 with the Q2 2027 launch date intact.
Research onlyNot in the portfolio.
Key figures from the filings · Technology
Quarter to 30 September 2026, filed 5 November 2026; valuation at the 13 November 2026 close
- Revenue, latest quarter ($M)
- 0.2
- Revenue, change on a year (%)
- −61.6
- Gross margin (%)
- 34.9
- Operating margin (%)
- −11215.1
- Net cash, cash less debt ($M)
- 149
- Enterprise value to sales (×)
- 81.0
All filed numbers
What Quantum-Si reports to the SEC in its quarterly and annual filings. Each group states its period and filing date once; a figure dated otherwise says so. Built from the filings known on .
| Quarter to | Revenue ($M) | On a year (%) | Gross margin (%) | Operating margin (%) |
|---|---|---|---|---|
| first filed | 0.2 | −61.6 | 34.9 | −11215.1 |
| first filed | 0.3 | −41.8 | 50.0 | −7450.3 |
| first filed | 0.3 | −69.4 | 28.7 | −9322.9 |
| first filed | 0.5 | −62.2 | 27.1 | −4677.2 |
| first filed | 0.6 | −29.9 | 35.1 | −7205.3 |
| first filed | 0.6 | −5.0 | 59.4 | −5096.4 |
| Pre-tax income ($M) | −22.3 |
| Net income ($M) four quarters: −85.1 | −22.3 |
| Diluted shares, change on a year (%) against the quarter to 30 September 2025 | +4.8 |
| Operating cash flow ($M) | −80.9 |
| Capital spending ($M) | Not available |
| Free cash flow ($M) | Not available |
| Cash and short-term investments ($M) | 149 |
| Debt ($M) | None reported |
| Net cash, cash less debt ($M) no debt reported | 149 |
| Deferred revenue ($M) +4.3% on a year | 0.1 |
| Backlog, orders not yet delivered ($M) | Not reported |
| Receivables ($M) | 0.1 |
| Inventory ($M) | 1.6 |
| Shareholders' equity ($M) | 160 |
| Market value ($M) | 252 |
| Enterprise value, market value plus net debt ($M) no debt reported | 102 |
| Enterprise value to sales (×) no debt reported | 81.0 |
| Enterprise value to operating income (×) | Not meaningful |
| Price to earnings (×) | Not meaningful |
| Price to book value (×) | 1.6 |
| Free-cash-flow yield (%) | Not available |
Short interest (FINRA, settled 15 October 2026, published 26 October 2026): 6.0% of shares outstanding sold short, 1.0 days of average trading to cover, +11.6% since the previous report.
| Window | Bought | Sold |
|---|---|---|
| 90 daysfrom | $0 | $40K |
| 12 monthsfrom | $564K | $495K |
The thesis
Quantum-Si's shares are more likely to lag the S&P 500 than lead it over the next three months. The Proteus protein sequencer is guided to launch in the second quarter of 2027, and 2026 revenue is guided to about $1.0M, so sales say little until launch. The company's target of detecting all 20 amino acids by year-end 2026 is the next test of the schedule.
The third-quarter report on 5 November 2026 kept the launch date and the revenue guide. Revenue was $212K, below the $280K analyst estimate and below the $552K of a year earlier. Net loss was $22.3M (Form 8-K, 5 November 2026). The shares closed at $1.17 that day, against $1.29 on 4 November 2026, then recovered to $1.33 on 6 November 2026 and ended at $1.27 on 11 November 2026.
The report also cut spending. Quantum-Si lowered its 2026 adjusted operating expense guide to $87.0M or less from $98.0M or less, and its total cash usage guide to $87.0M or less from $93.0M or less. Cash and marketable securities were $149.4M on 30 September 2026, which management expects to fund operations into the fourth quarter of 2028.
Bullish and bearish views on Quantum-Si Incorporated
The bull case on Quantum-Si Incorporated (QSI), in brief: chemistry milestones keep arriving. The bear case: the launch has already slipped once.
Bull case
- Chemistry milestones keep arriving. Quantum-Si reported 19 amino acids detected on 8 October 2026 and, at the 5 November 2026 report, expects the 20th before year-end. The commercial kit needs all 20.
- Large gain over the current instrument. The 29 September 2026 World HUPO (Human Proteome Organization) release reported a median of 30 times more alignments than Platinum Pro from a single chamber. The false discovery rate was 1.36%, against 6.58% for Platinum Pro.
- Lower spending extends the runway. The 5 November 2026 guide cuts 2026 cash usage to $87.0M or less from $93.0M or less. Management kept its runway into the fourth quarter of 2028.
- A pre-order program has opened. Quantum-Si announced it on 5 November 2026 to help customers plan adoption and secure priority access after launch.
- Listing risk is cleared for now. On 15 October 2026 Nasdaq confirmed the company regained compliance with the $1.00 minimum bid price.
Bear case
- The launch has already slipped once. On 13 August 2026 Quantum-Si moved Proteus to Q2 2027 to add an integrated instrument design cycle. The same release announced a 20% workforce reduction.
- Component supply is a new exposure. The 5 November 2026 release says AI-driven demand has extended lead times for some components. Management says it is ordering early and qualifying second sources, and does not expect an effect on the Q2 2027 launch.
- Revenue is shrinking. Third-quarter 2026 revenue of $212K compares with $552K in the third quarter of 2025 and missed the $280K analyst estimate. Cash and marketable securities fell from $169.9M on 30 June 2026 to $149.4M on 30 September 2026.
- 19 amino acids is a lab result. The 29 September 2026 HUPO figures came from an 18-amino-acid developmental kit. The release said the instrument, consumables and software were not fully optimized.
- A share-sale program is in place. Quantum-Si has a $100M at-the-market stock program and a $300M shelf registration filed in 2025. The third-quarter Form 10-Q, filed 5 November 2026, is where any sales and the share count appear.
Price setup
The shares closed at $1.27 on 11 November 2026. That is 29.8% below the 52-week intraday high of $1.81 set on 29 October 2026. The 52-week closing low is $0.70, on 29 July 2026. The 3-month change is 60.8%, from a close of $0.79 on 13 August 2026.
The close is above the 50-day average of $1.12 and the 200-day average of $0.96, adjusted daily closes as of 11 November 2026. The $1.00 level is the Nasdaq minimum bid price; a new deficiency notice follows 30 consecutive business days of closing bids below it.
The shares have swung between $1.17 and $1.37 in the six sessions since 4 November 2026, with no company announcement after the report. Three executives sold small blocks on the open market at $0.76 on 21 September to 22 September 2026, per SEC Form 4 filings, including 29,852 shares by CEO Jeffrey Hawkins.
Catalysts ahead
- ~31 December 2026 (est.): Company target for detecting all 20 amino acids. The commercial kit needs all 20. Reaching the target on time after the 19-amino-acid result supports the Q2 2027 launch; missing it points to another slip.
- ~30 June 2027 (est.): Proteus commercial launch, guided for Q2 2027. The event the case depends on. It shows whether the interim performance gap over Platinum Pro holds on a full-coverage kit and a manufactured instrument.
What would change the view
A daily close above $1.49, over the 9 November 2026 close of $1.37, which would show the shares leading the S&P 500 again. A result pointing the same way: detection of all 20 amino acids announced before 31 December 2026 with the Q2 2027 launch date intact.
What it trades with
Quantum-Si trades on its own news flow, not with an index or sector. The 24% jump on 29 September 2026 followed the HUPO data release. Peers in protein analysis and life-science tools, and small-cap healthcare names with high retail attention, are the closest comparison. The sample of moves is too small to measure a stable relationship.
The evidence, claim by claim (8)
- Q3 2026 revenue was $212K vs $552K in Q3 2025 and a $280K analyst estimate; net loss was $22.3M; adjusted EBITDA was −$17.0M. Q3 2026 results, Form 8-K Ex. 99.1 · as of
- Cash, cash equivalents and marketable securities were $149.4M; management expects them to fund operations into Q4 2028. Q3 2026 results, Form 8-K Ex. 99.1 · as of
- FY2026 guidance: revenue about $1.0M (reiterated); adjusted operating expenses $87.0M or less (from $98.0M); total cash usage $87.0M or less (from $93.0M). Q3 2026 results, Form 8-K Ex. 99.1 · as of
- Company is confident in Proteus commercial launch in Q2 2027, expects the 20th amino acid before year-end, and opened a Proteus pre-order program. Q3 2026 results, Form 8-K Ex. 99.1 · as of
- AI-driven demand has extended lead times for some Proteus components; management does not expect an effect on the Q2 2027 launch. Q3 2026 results, Form 8-K Ex. 99.1 · as of
- Interim Proteus data showed a median of 30x more alignments than Platinum Pro from a single chamber and a false discovery rate of 1.36% vs 6.58%. Quantum-Si press release, World HUPO 2026 · as of
- CEO Jeffrey Hawkins sold 29,852 shares on the open market at an average $0.76 on 21 September to 22 September 2026. SEC Form 4 · as of
- Nasdaq confirmed Quantum-Si regained compliance with the $1.00 minimum bid price requirement. Quantum-Si press release, Form 8-K · as of
Sources