QSI Stock — QuantumSi Inc

QuantumSi Inc (QSI)

Updated October 16, 2026.

QSI is a Stock. Total return is -88.7% over the past 5.9 years, 219.8 points behind SPY at 131.1%.

Quantum-Si Inc is a life sciences company that develops a proprietary single-molecule detection platform for next-generation protein sequencing (NGPS). The company sells NGPS instruments, library preparation kits, sequencing kits, and cloud-based analysis software to enable protein analysis at the amino acid level. The company does not currently have an established distribution schedule.

QSI performance versus SPY

Price and return data through 2026-10-16.

Total return is -88.7% over the past 5.9 years, 219.8 points behind SPY at 131.1%. Over the past year its total return — price change plus distributions reinvested — is -55.9%. Its deepest 1-year drawdown was 72.8%.

QSI key facts

Asset type

Stock

Asset class

Equity

Inception date

11/13/2020

Distribution frequency

None

Last close

$1.12 (as of 2026-10-16)

Market cap

$222,819,981

Average volume

7596686.0

Beta

3.218

Payout ratio

0.0%

EPS

$-0.56

How Dividend Vision calculates yield and returns

Distribution rate (the posted rate) uses calculation basis unavailable. Issuer rates can use a different denominator and date, including ex-date NAV. Trailing-12-month yield is the sum of split-adjusted cash distributions with ex-dates in the last 12 months, divided by the published price. It lags a recent raise or cut. Total return uses split-adjusted close with distributions reinvested on the ex-dividend date (a modeling convention, not the cash-settlement date) from the first stored bar on or after inception through the latest bar, compared with the same window on the benchmark. That is the security's total return, not your personal gain/loss.

Yield and safety methodology · Distribution rate methodology · Distribution Safety Score methodology

Sources and review

Primary sources: prices and distributions from Dividend Vision, derived from vendor EOD data.

Reviewed by Bert Sweet, CEO and Co-owner of Dividend Vision. Methodology: Distribution Safety Score.

QSI risks and drawbacks

Total return has trailed SPY over the available window. The deepest 1-year drawdown on record here is 72.8%.

Who may consider QSI — and who may not

It is a weaker fit for investors who need monthly cash flow (QSI does not currently distribute); investors whose main goal is matching SPY total return. This is educational context, not a recommendation to buy or sell.

More on QSI

• All tickers starting with Q

Tagged: Healthcare.

Frequently asked questions