Who invested in Callsign

2 rounds we have observed, with the 3 investors named in them. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it.

Cybersecurity

Funding summaryUpdated 26 Oct 2026

$109Mraised across 2 rounds since 2017, from 2 sources

$35MSeries A$74MRound

Latest round: Round, $74MJun 2023
Step-upi: 2.1×
Investors: 3 (1 led)

See who backed them

The funding story

Each circle is a round, placed by date and sized by amount. The line above is the running total.

201820192020202120222023

$35MSeries A$74MRound

First round: Series A, $35M
Biggest round: $74M
Between rounds: 5.9 years

The rounds

Jun 2023
Round$74M
No investor was named in the report.
Shares issued, filed with Companies House (SH01); no report of this raise yet
Jul 2017
Series A$35M3 new
- AccelLead
- NightDragon
- PTB Ventures/ Allegis
Reported by TechCrunch

Funding filed with regulators

Callsign filed one raise, $74M in all. Filings say how much was sold and to how many investors; they never name the investors.

Jun 2023$74MUK share allotment

Who was in which round

The busiest backers across the latest rounds. A filled square is a round they joined; a dark one, a round they led.

Series A2017Round2023

AccelL

NightDragonPTB Ventures/ Allegis

Everyone who backed them

AccelVC firm1round, led 1

NightDragonVC firm1round

PTB Ventures/ Allegisno record of our own yet1round

Missing a round, or an investor who was in one? Tell us.

Also claim to have backed them

These 7 firms list Callsign as a portfolio company on their own websites, but no report of a round names them. They are the firms' own claims, kept apart from the rounds above.