A well-known digital currency investor is suing a Hong Kong website operator for some US$570,000 (HK$4.4 million) over an alleged breach of agreement, court documents state. In a writ filed to Hong Kong’s High Court on Wednesday, Roger Keith Ver, registrant and administrator of the domain name bitcoin.com, claimed OKEX Fintech Company, which provided online services for local and international bitcoin trading, had broken their contractual obligations. Ver stated that he entered into a contract with OKEX on December 15, 2014 , in which the local firm agreed to manage and operate bitcoin.com on Ver’s behalf through the domain name Okcoin.com. OKEX’s services included redesigning the bitcoin.com website, performing search engine optimisation and acquiring advertisers. Hong Kong Bitcoin exchange hacked, US$66m stolen: thieves may have exploited market closure during typhoon Ver claimed the agreement dictated that both parties would cooperate for a minimum of five years and would split revenues. However, he stated the online service company refused to pay the monthly sums just three months into the contract. The well-known bitcoin personality is now seeking US$10,000 (HK$77,557) for each of remaining 57 months of the agreed five-year contract – totalling US$570,000. Ver also claimed that the contested version of the contract was a forgery. He said it included a clause allowing the local company to cancel the contract with six months’ notice, which was not in the original, and his digital signature had been copied and pasted into the document. Ver requested that the court declare the contested version of the contract a forgery. Mainland businessman Xu Mingxing, founder and chief executive officer of Okcoin, was named as a co-defendant in the lawsuit. Bitcoins began circulating in 2009 and have since become the most prominent of several digital currencies. The electronic money is transferred independently of traditional banks, but some cloak-and-dagger transactions have aroused concern among financial authorities worldwide. In an interview in 2013, Ver told the South China Morning Post that efforts to disrupt the digital currency money market would be futile.