Hal Finney
As the first person to use bitcoin after Satoshi, Finney is seen as an instrumental architect of bitcoin and its foundations. He passed away in August 2014 having succumbed to amyotrophic lateral sclerosis, or ALS, which paralysed him in August 2009.
The computer scientist worked closely with the creator of Pretty Good Privacy (PGP), a digital data encryption program developed in the 1990s that would eventually become a key cog in the bitcoin machine. He was so intrigued when the bitcoin whitepaper was released several years later, that he became the first person besides Satoshi to run bitcoin, mining ‘block 70-something’, and was the recipient of the first bitcoin transaction after Satoshi sent 10 bitcoins to him as a test.
Although Finney conversed with Satoshi via email to help filter out initial bugs, he claimed he never discovered Satoshi’s identity, and had to deny that he was the mysterious founder on several occasions.
In a forum post in March 2013, Finney said the true identity of Satoshi was a mystery, but that he believed, when he was interacting with him, he was dealing with a ‘young man of Japanese ancestry who was very smart and sincere’.
Phil Zimmerman
Zimmerman was the man behind PGP, which he developed (with the help of Finney) years before bitcoin emerged, after recognising that cryptography ‘is about the right to privacy, freedom of speech, freedom of political association, freedom of the press, freedom from unreasonable search and seizure, freedom to be left alone,’ according to the University of Pittsburgh.
PGP was created when email was, as Zimmerman put it, ‘a novelty’ and not mainstream. PGP is used for signing, encrypting, and decrypting messages and files. With respect to cryptocurrency, PGP allows users to create a pair of keys – a ‘public’ key for encryption and a ‘private’ key for decryption. This is at the heart of the technology that cryptocurrencies are based on, known as blockchain, and is the reason why users can circumnavigate the middle-men like banks that manage traditional transactions in a secure manner.
Nick Szabo
The computer scientist has had to deny claims he is Satoshi for years, having been considered a likely candidate after creating what is widely seen as the precursor to bitcoin, ‘bit gold’. Bit gold was made in 1998 – a decade before the bitcoin whitepaper – and, in a nutshell, was a mechanism (which never quite took off) designed to facilitate a decentralised digital currency.
Looking at Szabo’s description of the bit gold protocol and why he was pursuing it, it is unsurprising he has and is still seen by many as the founder of bitcoin.
‘It would be very nice if there were a protocol whereby unforgivably costly bits could be created online with minimal dependence on trusted third parties, and then securely stored, transferred, and assayed with similar minimal trust. Bit gold.’
Craig Wright
Unlike those who have had to deny claims made by other people, Australian entrepreneur Wright surprised the world when he told the three media organisations he was Satoshi in May 2016. He provided ‘technical proof’ to the BBC by digitally signing messages using keys made in the early days of bitcoin, ones that were synched with the blocks used by Satoshi to send 10 bitcoins to Finney in January 2009.
Although he was backed by two figures from the Bitcoin Foundation (a non-profit aiming to standardise, protect and promote the use of bitcoin), he failed to follow-through on his promise to prove he possessed Satoshi's cryptographic keys by moving bitcoins from the first blocks ever mined by Satoshi.
In a rather undignified fall from grace, Wright later published a blog that said he ‘broke’ as he prepared to publish the proof, stating ‘I do not have the courage. I cannot’. Still, there are many in the community that believe his claim based on the other evidence, but the bottom line is that Wright has failed to undeniably prove he is Satoshi and win round the bitcoin buyers.
But why create something and not take the credit?
Firstly, as a truly independent system free from any central body, the fact it has no official owner or recognised creator beyond the pseudonym is quite fitting. The bitcoin community, therefore, makes decisions and shapes its future through consensus – arguably making bitcoin a truly democratic currency.
Secondly, although Satoshi has barely appeared since vanishing from the internet in 2011, when they had ‘moved on to other things’, it is likely Satoshi walked away with one of the largest wallets of bitcoin in existence to this date. While there have been estimates over the precise figure, it has been reported to be up to 1 million bitcoins, or 5% of all the bitcoin that will ever exist. With that much, Satoshi has the ability to heavily influence the market and anonymity would allow the founder, for example, to sell without sparking havoc amongst other bitcoin users.
To find out more about what moves the cryptocurrency's price, take a look at our 'how to trade bitcoin' guide.
Thirdly, with the legality of bitcoin thrown into doubt over its decade-long life on several occasions, Satoshi may have been keen to not be seen as the creator of something that is designed to operate outside of government control and previously used on sites like Silk Road.
Cryptocurrency: possession is ten tenths of the law
The real person (or persons) behind Satoshi could prove their identity by using the first PGP keys that control access to the bitcoins mined in the early days (no bitcoins have ever left Satoshi’s wallet). But some argue the founder would have to prove they have access to the ‘Genesis Block’ (the first block in the blockchain) to truly convince the community, or move bitcoin from that block.
Still, we know Satoshi is a world-class coder (which is the main argument for it being a group rather than an individual), speaks fluent English, and has disrupted the way the world understands money using a technology that will go well beyond bitcoin and the cryptocurrencies it has gone on to inspire.