Coinbase Cartel Claims Data Breach at Dual-Listed Insurer Tower Limited

A dual-listed insurer, Tower Limited, is investigating a claim by a ransomware group called Coinbase Cartel that it stole company data. Tower, also known as Tower Insurance, has not confirmed a data breach, but is working with external cybersecurity consultants and has notified relevant authorities. The company's response has been consistent, saying it is aware of unverified information posted on cyber forums and will notify affected customers and stakeholders if any are identified.

The group behind the claim, Coinbase Cartel, has been active since September 2025 and has claimed 207 victims in 2026, with a preference for Western targets, particularly in the US, France, and the UAE. It is an 'encryption-free data extortion group' that steals data and threatens to publish it rather than locking victims out of their systems with ransomware payloads.

The investigation into the claim has taken weeks, not days, as forensic verification of a leak-site claim is slower than most outsiders expect. Investigators have to establish whether the data sample posted by the group actually originated inside the victim's own systems or was scraped from a prior breach, purchased from a broker, or stitched together from multiple smaller leaks.