T-Mobile Sued Over SIM Attack That Resulted in Loss of $450K in Bitcoin

The plaintiff lost 15 bitcoin after an interaction with a T-Mobile customer who had been victim of a SIM-swapping attack.

AccessTimeIconFeb 12, 2021 at 11:15 a.m. UTC
Updated Sep 14, 2021 at 12:11 p.m. UTC

T-Mobile is being sued by a customer as a result of a SIM attack that resulted in over losses of over $450,000 in cryptocurrency.

  • The plaintiff, Calvin Cheng, lost 15 bitcoin after an interaction with Brandon Buchanan, T-Mobile customer and co-founder of investment fund Iterative Capital, who had been victim of a SIM-swapping attack.
  • California resident Cheng received a message via Telegram that he believed was from Buchanan offering him an above market value rate for 15 BTC in May 2020.
  • The plaintiff's attorneys claim that T-Mobile's "systemic and repeated failures" to protect customers' sensitive information despite increasingly frequent SIM attacks is to blame.
  • The complaint, filed Monday in the Southern District of New York, alleges T-Mobile violated federal laws and was negligent in its hiring and training of customer service personnel.
  • T-Mobile has claimed that it maintains the highest standard of authentication procedures to protect its customers in the face of account takeover fraud.
  • In a similar case, crypto investor Michael Terpin is suing AT&T for $23.8 million, the dollar value of cryptocurrencies that he had stolen in 2018.


Please note that our privacy policy, terms of use, cookies, and do not sell my personal information has been updated.

The leader in news and information on cryptocurrency, digital assets and the future of money, CoinDesk is a media outlet that strives for the highest journalistic standards and abides by a strict set of editorial policies. CoinDesk is an independent operating subsidiary of Digital Currency Group, which invests in cryptocurrencies and blockchain startups. As part of their compensation, certain CoinDesk employees, including editorial employees, may receive exposure to DCG equity in the form of stock appreciation rights, which vest over a multi-year period. CoinDesk journalists are not allowed to purchase stock outright in DCG.

Learn more about Consensus 2024, CoinDesk’s longest-running and most influential event that brings together all sides of crypto, blockchain and Web3. Head to consensus.coindesk.com to register and buy your pass now.