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.

Feb 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.


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