"That appeared to be that, until a year later when Mr Buterin received a letter from Mr Wright's attorney. The legal notice, dated 12 April, said Mr Wright intends to sue Mr Buterin in the UK for defamation."

https://www.independent.co.uk/life-style/gadgets-and-tech/bitcoin-inventor-craig-wright-defamation-cryptocurrency-vitalik-buterin-a8970436.html