Satoshi Nakamoto is the name used by the unknown person or persons who developed bitcoin, authored the bitcoin white paper, and created and deployed bitcoin's original reference implementation. As part of the implementation, they also devised the first blockchain database. In the process, they were the first to solve the double-spending problem for digital currency using a peer-to-peer network. They were active in the development of bitcoin up until December 2010.
|Born||5 April 1975 (claimed)|
|Known for||Inventing bitcoin, implementing the first blockchain, deploying the first decentralized digital currency|
|Fields||Digital currencies, computer science, cryptography|
Speculation about the true identity of Nakamoto has mostly focused on a number of cryptography and computer science experts of non-Japanese descent, living in the United States and various European countries.
Development of bitcoin
In October 2008, Nakamoto published a paper on the cryptography mailing list at metzdowd.com describing the bitcoin digital currency. It was titled "Bitcoin: A Peer-to-Peer Electronic Cash System". In January 2009, Nakamoto released the first bitcoin software that launched the network and the first units of the bitcoin cryptocurrency, called bitcoins. Satoshi Nakamoto released the Version 0.1 of bitcoin software on Sourceforge on 9 January 2009.
Nakamoto claimed that work on the writing of the code began in 2007. Nakamoto knew that due to its nature, the core design would have to be able to support a broad range of transaction types. The implemented solution enabled specialized codes and data fields from the start through the use of a predicative script.
Nakamoto created a website with the domain name bitcoin.org and continued to collaborate with other developers on the bitcoin software until mid-2010. Around this time, he handed over control of the source code repository and network alert key to Gavin Andresen, transferred several related domains to various prominent members of the bitcoin community, and stopped his involvement in the project. Until shortly before his absence and handover, Nakamoto made all modifications to the source code himself.
On 3 January 2009, the bitcoin network came into existence with Satoshi Nakamoto mining the genesis block of bitcoin (block number 0), which had a reward of 50 bitcoins. Embedded in the coinbase transaction of this block was the text:
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks.
The text refers to a headline in The Times published on 3 January 2009. This note has been interpreted as both a timestamp of the genesis date and a derisive comment on the instability caused by fractional-reserve banking.:18
Except for test transactions, Nakamoto's coins remain unspent since mid January 2009. At bitcoin's peak in December 2017, these were worth over US$19 billion, making Nakamoto possibly the 44th richest person in the world at the time.
Characteristics and identity
Nakamoto has not disclosed any personal information when discussing technical matters. He provided some commentary on banking and fractional-reserve banking. On his P2P Foundation profile as of 2012, Nakamoto claimed to be a 37-year-old male who lived in Japan, but some speculated he was unlikely to be Japanese due to his use of perfect English and his bitcoin software not being documented or labelled in Japanese.
Occasional British English spelling and terminology (such as the phrase "bloody hard") in both source code comments and forum postings led to speculation that Nakamoto, or at least one individual in the consortium claiming to be him, was of Commonwealth origin. Moreover, the first bitcoin block that could only be mined by Satoshi contains the encoded text
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks which implies that he was reading London's The Times newspaper at the time of the inception of bitcoin.:18
Stefan Thomas, a Swiss coder and active community member, graphed the time stamps for each of Nakamoto's bitcoin forum posts (more than 500); 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. This was between 2 p.m. and 8 p.m. Japanese time, suggesting an unusual sleep pattern for someone presumably living in Japan. As this pattern held true even on Saturdays and Sundays, it suggested that Nakamoto was asleep at this time.
Nakamoto's initial email to Dai is dated 22 August 2008; the metadata for this PDF (
pdftk bitcoin.pdf dump_data) yields as the
CreationDate the value
20081003134958-07'00' – this implies 3 October 2008 or a bit over a month later, which is consistent with the local date mentioned in the Cypherpunk mailing list email. This is an earlier draft than the final draft on
bitcoin.org, which is dated
20090324113315-06'00' or 24 March 2009; the timezone differs: −7 vs −6.
There is still doubt about the real identity of Satoshi Nakamoto.
Hal Finney (4 May 1956 – 28 August 2014) was a pre-bitcoin cryptographic pioneer and the first person (other than Nakamoto himself) to use the software, file bug reports, and make improvements. He also lived a few blocks from Dorian Nakamoto's family home, according to Forbes journalist Andy Greenberg. Greenberg asked the writing analysis consultancy Juola & Associates to compare a sample of Finney's writing to Satoshi Nakamoto's, and they found that it was the closest resemblance they had yet come across (including the candidates suggested by Newsweek, Fast Company, The New Yorker, Ted Nelson and Skye Grey). Greenberg theorized that Finney may have been a ghostwriter on behalf of Nakamoto, or that he simply used his neighbor Dorian's identity as a "drop" or "patsy whose personal information is used to hide online exploits". However, after meeting Finney, seeing the emails between him and Nakamoto and his bitcoin wallet's history (including the very first bitcoin transaction from Nakamoto to him, which he forgot to pay back) and hearing his denial, Greenberg concluded that Finney was telling the truth. Juola & Associates also found that Nakamoto's emails to Finney more closely resemble Nakamoto's other writings than Finney's do. Finney's fellow extropian and sometimes co-blogger Robin Hanson assigned a subjective probability of "at least" 15% that "Hal was more involved than he's said", before further evidence suggested that was not the case.
In December 2013, a blogger named Skye Grey linked Nick Szabo to the bitcoin whitepaper using a stylometric analysis. Szabo is a decentralized currency enthusiast and published a paper on "bit gold", which is considered a precursor to bitcoin. He is known to have been interested in using pseudonyms in the 1990s. In a May 2011 article, Szabo stated about the bitcoin creator: "Myself, Wei Dai, and Hal Finney were the only people I know of who liked the idea (or in Dai's case his related idea) enough to pursue it to any significant extent until Nakamoto (assuming Nakamoto is not really Finney or Dai)."
Detailed research by financial author Dominic Frisby provides much circumstantial evidence but, as he admits, no proof that Satoshi is Szabo. Speaking on RT's The Keiser Report, he said "I've concluded there is only one person in the whole world that has the sheer breadth but also the specificity of knowledge and it is this chap ...". However, Szabo has denied being Satoshi. In a July 2014 email to Frisby, he said: 'Thanks for letting me know. I'm afraid you got it wrong doxing me as Satoshi, but I'm used to it'. Nathaniel Popper wrote in the New York Times that "the most convincing evidence pointed to a reclusive American man of Hungarian descent named Nick Szabo."
In a high-profile 6 March 2014 article in the magazine Newsweek, journalist Leah McGrath Goodman identified Dorian Prentice Satoshi Nakamoto, a Japanese American man living in California, whose birth name is Satoshi Nakamoto, as the Nakamoto in question. Besides his name, Goodman pointed to a number of facts that circumstantially suggested he was the bitcoin inventor. Trained as a physicist at Cal Poly University in Pomona, Nakamoto worked as a systems engineer on classified defense projects and computer engineer for technology and financial information services companies. Nakamoto was laid off twice in the early 1990s and turned libertarian, according to his daughter, and encouraged her to start her own business "not under the government's thumb." In the article's seemingly biggest piece of evidence, Goodman wrote that when she asked him about bitcoin during a brief in-person interview, Nakamoto seemed to confirm his identity as the bitcoin founder by stating: "I am no longer involved in that and I cannot discuss it. It's been turned over to other people. They are in charge of it now. I no longer have any connection." The article's publication led to a flurry of media interest, including reporters camping out near Dorian Nakamoto's house and subtly chasing him by car when he drove to do an interview. However, during the subsequent full-length interview, Dorian Nakamoto denied all connection to bitcoin, saying he had never heard of the currency before, and that he had misinterpreted Goodman's question as being about his previous work for military contractors, much of which was classified. In a Reddit "ask-me-anything" interview, he claimed he had misinterpreted Goodman's question as being related to his work for Citibank. Later that day, the pseudonymous Nakamoto's P2P Foundation account posted its first message in five years, stating: "I am not Dorian Nakamoto." However, it is generally believed that Nakamoto's P2P Foundation account had been hacked, and the message was not sent by him.
On 8 December 2015, Wired wrote that Craig Steven Wright, an Australian academic, "either invented bitcoin or is a brilliant hoaxer who very badly wants us to believe he did". Craig Wright took down his Twitter account and neither he nor his ex-wife responded to press inquiries. The same day, Gizmodo published a story with evidence obtained by a hacker who supposedly broke into Wright's email accounts, claiming that Satoshi Nakamoto was a joint pseudonym for Craig Steven Wright and computer forensics analyst David Kleiman, who died in 2013. Wright's claim was supported by Jon Matonis (former director of the Bitcoin Foundation) & bitcoin developer Gavin Andresen as well as cryptographer Ian Grigg.
A number of prominent bitcoin promoters remained unconvinced by the reports. Subsequent reports also raised the possibility that the evidence provided was an elaborate hoax, which Wired acknowledged "cast doubt" on their suggestion that Wright was Nakamoto. Bitcoin developer Peter Todd said that Wright's blog post, which appeared to contain cryptographic proof, actually contained nothing of the sort. Bitcoin developer Jeff Garzik agreed that evidence publicly provided by Wright does not prove anything, and security researcher Dan Kaminsky concluded Wright's claim was "intentional scammery".
In May 2019 it was reported that Wright was using UK libel law to sue people who denied he was the inventor of bitcoin.
In 2019 Wright registered US copyright for the bitcoin white paper and the code for Bitcoin 0.1. Wright's team claimed this was "government agency recognition of Craig Wright as Satoshi Nakamoto"; the United States Copyright Office issued a press release clarifying that this was not the case.
Other claimed candidates
In a 2011 article in The New Yorker, Joshua Davis claimed to have narrowed down the identity of Nakamoto to a number of possible individuals, including the Finnish economic sociologist Dr. Vili Lehdonvirta and Irish student Michael Clear, then a graduate student in cryptography at Trinity College Dublin and now a post-doctoral student at Georgetown University. Clear strongly denied he was Nakamoto, as did Lehdonvirta.
In October 2011, writing for Fast Company, investigative journalist Adam Penenberg cited circumstantial evidence suggesting Neal King, Vladimir Oksman and Charles Bry could be Nakamoto. They jointly filed a patent application that contained the phrase "computationally impractical to reverse" in 2008, which was also used in the bitcoin white paper by Nakamoto. The domain name bitcoin.org was registered three days after the patent was filed. All three men denied being Nakamoto when contacted by Penenberg.
In May 2013, Ted Nelson speculated that Nakamoto is really Japanese mathematician Shinichi Mochizuki. Later, an article was published in The Age newspaper that claimed that Mochizuki denied these speculations, but without attributing a source for the denial.
A 2013 article in Vice listed Gavin Andresen, Jed McCaleb, or a government agency as possible candidates to be Nakamoto. Dustin D. Trammell, a Texas-based security researcher, was suggested as Nakamoto, but he publicly denied it.
In 2013, two Israeli mathematicians, Dorit Ron and Adi Shamir, published a paper claiming a link between Nakamoto and Ross Ulbricht. The two based their suspicion on an analysis of the network of bitcoin transactions, but later retracted their claim.
Some have considered that Nakamoto might be a team of people: Dan Kaminsky, a security researcher who read the bitcoin code, said that Nakamoto could either be a "team of people" or a "genius"; Laszlo Hanyecz, a developer who had emailed Nakamoto, had the feeling the code was too well designed for one person.
A 2017 article published by a former SpaceX intern espoused the possibility of SpaceX and Tesla CEO Elon Musk being the real Satoshi, based on Musk's technical expertise with financial software and history of publishing whitepapers. However, in a tweet dated 28 November 2017, Musk denied the claim.
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