Quantum-Si

Biotech tools / protein sequencingUSA

New to Unitard

📉 Public < $1B

Peak $1.46 BillionToday

−79%

from peak

🦄
Became a unicorn
2021
📈
Peak valuation
$1.46 Billion ’21
💔
Became a Unitard
2022
💸
Last valuation
~$306M

Current status

Public (Nasdaq: QSI)

Live · QSI· NasdaqGM

as of 2026-10-23

$1.40▲ 25.00% today

≈ $306 Million market cap · −79.0% from peak

The rise & fall

5 moments · 2013–2024

The key moments, with employee sentiment along the way.

2013

Founded in Jonathan Rothberg's startup foundry

The DNA-sequencing pioneer's 4Catalyzer incubator sets out to do for proteins what cheap genome sequencing did for DNA.

GenomeWeb

Jun 2021

The peak: a $1.46B SPAC debut$1.46B

Merges with HighCape Capital's SPAC on the back of an oversubscribed $425M PIPE — with the chips still years from market.

GlobeNewswire

2022

Slips out of the club

Commercial traction comes slowly, and the pre-revenue premium evaporates as the market turns on biotech-tools SPACs.

GenomeWeb

2022–24

From the inside · Glassdoor reviews, 2022–24

Glassdoor reviews across the slide counted repeated layoff rounds — unusually frequent for a company its size — with employees pointing to shifting priorities and abandoned projects, and describing a leadership team slow to set a clear direction.

Today

Still in the club — and still trading

Live · QSI · NasdaqGMas of 2026-10-23

$1.40▲ 25.00% today≈ $306M cap · −79.0% from peak

💬 entries paraphrase anonymous, unverified reviews posted publicly on Glassdoor ↗; dated facts carry their source.

How it happened

Quantum-Si is developing semiconductor-chip-based 'next-generation protein sequencing,' aiming to do for proteins what cheap DNA sequencing did for genomics, and went public in June 2021 via a SPAC merger with HighCape Capital at a $1.46B valuation, backed by an oversubscribed $425M PIPE. Commercial traction came slowly and the market soured on pre-revenue biotech-tools SPACs; the stock fell about 88% to around $180M.

Source: GlobeNewswire / GenomeWeb / stockanalysis ($1.46B pro forma equity value via HighCape Capital SPAC, June 2021, ~$425M PIPE; ~$180M market cap by 2026)

Founder

Jonathan Rothberg
Founder & Executive Chairman (interim CEO 2022); current CEO is Jeff Hawkins
Still there — Founder and ChairmanLinkedIn ↗

Current roles as self-reported on LinkedIn, retrieved 2026-08-21. See our methodology.

Disclosed investors (6)

Historical funding participation; lists may be incomplete and do not establish current ownership or investor losses.

* Lead in a funding round · Crunchbase ↗ · 2026-10-13 · Methodology · Leaderboard