Quantum-Si

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About QSI

Quantum-Si, Inc. is a life sciences company focused on revolutionizing the growing field of proteomics. It engages in the development of a proprietary universal single-molecule detection platform to enable Next-Generation Protein Sequencing (NGPS), the ability to sequence proteins in a massively parallel fashion. 

CEO
Jeffrey Alan Hawkins
CEOJeffrey Alan Hawkins
Employees
149
Employees149
Headquarters
Branford, Connecticut
HeadquartersBranford, Connecticut
Founded
2013
Founded2013
Employees
149
Employees149

QSI Key Statistics

Market cap
283.37M
Market cap283.37M
Price-Earnings ratio
-1.99
Price-Earnings ratio-1.99
Dividend yield
Dividend yield
Average volume
5.07M
Average volume5.07M
High today
High today
Low today
Low today
Open price
$1.23
Open price$1.23
Volume
20.06K
Volume20.06K
52 Week high
$3.10
52 Week high$3.10
52 Week low
$0.9499
52 Week low$0.9499

Stock Snapshot

With a market cap of 283.37M, Quantum-Si(QSI) trades at $1.28. The stock has a price-to-earnings ratio of -1.99.

On 2026-01-23, Quantum-Si(QSI) shares started trading at $1.23, with intraday highs of — and lows of —.

Trading volume for Quantum-Si(QSI) stock has reached 20.06K, versus its average volume of 5.07M.

Over the past 52 weeks, Quantum-Si(QSI) stock has traded between a high of $3.10 and a low of $0.95.

Over the past 52 weeks, Quantum-Si(QSI) stock has traded between a high of $3.10 and a low of $0.95.

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