<Tr> <Td> 5 February 2018 </Td> <Td> $6,200 </Td> <Td> Bitcoin's price drops 50 percent in 16 days, falling below $7,000 . </Td> </Tr> <P> "Satoshi Nakamoto" is presumed to be a pseudonym for the person or people who designed the original bitcoin protocol in 2008 and launched the network in 2009 . Nakamoto was responsible for creating the majority of the official bitcoin software and was active in making modifications and posting technical information on the bitcoin forum . Investigations into the real identity of Satoshi Nakamoto were attempted by The New Yorker and Fast Company . The New Yorker's investigation brought up at least two possible candidates: Michael Clear and Vili Lehdonvirta . Fast Company's investigation brought up circumstantial evidence linking an encryption patent application filed by Neal King, Vladimir Oksman and Charles Bry on 15 August 2008, and the bitcoin.org domain name which was registered 72 hours later . The patent application (#20100042841) contained networking and encryption technologies similar to bitcoin's, and textual analysis revealed that the phrase "...computationally impractical to reverse" appeared in both the patent application and bitcoin's whitepaper . All three inventors explicitly denied being Satoshi Nakamoto . In May 2013, Ted Nelson speculated that Japanese mathematician Shinichi Mochizuki is Satoshi Nakamoto . Later in 2013 the Israeli researchers Dorit Ron and Adi Shamir pointed to Silk Road - linked Ross William Ulbricht as the possible person behind the cover . The two researchers based their suspicion on an analysis of the network of bitcoin transactions . These allegations were contested and Ron and Shamir later retracted their claim . </P> <P> Nakamoto's involvement with bitcoin does not appear to extend past mid-2010 . In April 2011, Nakamoto communicated with a bitcoin contributor, saying that he had "moved on to other things". </P> <P> Stefan Thomas, a Swiss coder and active community member, graphed the time stamps for each of Nakamoto's 500 - plus bitcoin forum posts; the resulting chart showed a steep decline to almost no posts between the hours of 5 a.m. and 11 a.m. Greenwich Mean Time . Because this pattern held true even on Saturdays and Sundays, it suggested that Nakamoto was asleep at this time, and the hours of 5 a.m. to 11 a.m. GMT are midnight to 6 a.m. Eastern Standard Time (North American Eastern Standard Time). Other clues suggested that Nakamoto was British: A newspaper headline he had encoded in the genesis block came from the UK - published newspaper The Times, and both his forum posts and his comments in the bitcoin source code used British English spellings, such as "optimise" and "colour". </P>

When did bitcoin start trading on the stock market