After concluding in December 2014 that regulators had legal authority over Bitcoin, the California Department of Business Oversight has decided not to exercise it.
The question of how and whether to regulate Bitcoin has confounded regulators around the world since it emerged in software form in 2009 from a paper authored by an anonymous computer scientist.
About 60,000 US businesses accept Bitcoin as currency, and it is used in more than 100,000 transactions a day.
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