Callsign is pioneering digital trust through proprietary technology that uniquely mimics the way humans identify each other in the real world. Positive identification of genuine users delivers privacy, safety and minimal friction whilst ensuring that bad actors are blocked. Through a simple Swipe or Type, users can be personally recognized to a 99.999% accuracy, delivering the highest fidelity AI based user recognition for the digital world.
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The Callsign annual revenue was $67.4 million in 2026.
Ian Welch is the Co-Founder and Chief Operating Officer of Callsign.
227 people are employed at Callsign.
Callsign is based in London, England.
The NAICS codes for Callsign are [518, 51, 511, 5112].
The SIC codes for Callsign are [73, 737].