The idea behind blockchain technology can be traced to 1991 when Stuart Haber and W. Scott Stornetta described the first work on a cryptographically secured chain of blocks. In 1992, they incorporated Merkle trees into the design allowing several documents to be collected into a block.
However, blockchain technology as we know it today gained significance from 2008 when a pseudonymous Satoshi Nakamoto published the Bitcoin white paper. Satoshi Nakamoto gave practical impetus to blockchain technology and solved the problem of double spending.
Since then, the identity of the person who invented blockchain technology has been a subject of speculation. Various people suspected to be the Nakamoto have denied the claim. They include:
Dorian Nakamoto
On 6 March 2014, Leah McGrath Goodman published an article in the Newsweek entitled “The Face Behind Bitcoin” in which she claimed that Dorian Nakamoto, a computer engineer, was the inventor of blockchain technology and bitcoin. She noted that Dorian Nakamoto was a Japanese man living in California whose real name was Satoshi Nakamoto. Dorian’s link with Japan further points to the possibility that he was indeed the inventor of the blockchain. The P2P Foundation profile of the pseudonymous Nakamoto identified him as a 37 year old man living in Japan. However, his use of perfect English suggested that he could not be living in Japan.
Goodman noted that circumstantial evidence showed that Dorian was the inventor of bitcoin and blockchain. When she asked Dorian about bitcoin, he seemed to confirm his identity by saying, “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.” Following increased media interests, Dorian claimed to have misunderstood Goodman’s question as relating to his work as a military contractor.
Nick Szabo
In a December 2013 blog post, Skye Grey used stylometric analysis to conclude that Nick Szabo was Satoshi Nakamoto. Szabo, a decentralized currency enthusiast had published a paper, bit gold, which was later followed by the bitcoin white paper. In the 1990s, Szabo liked using pseudonyms. Financial author, Dominic Frisby concluded that, “there is only one person in the whole world that has the sheer breadth and the specificity of knowledge and it is this chap.” Nathaniel Popper writing in the New York Times also concluded that “the most convincing evidence pointed to Nick Szabo, an American of Hungarian descent.”
Hal Finney
Hal Finney was a cryptographic pioneer prior to bitcoin. Other than Nakamoto, he was the first person to use bitcoin blockchain, make improvements and file bug reports. He was Dorian Nakamoto’s neighbour. On request of Andy Greenberg, writing analysis firm Juola & Associates compared samples of Finney’s writings with those of Nakamoto and concluded that they had the closest resemblance ever. Greenberg concluded that Finney may have used his neighbour, Dorian’s identity as a “drop” or was a ghostwriter on behalf of Nakamoto.
Steve Craig
While all those who have been suspected to be Nakamoto have denied it, Steve Craig, an Australian has claimed to be Nakamoto. However, he has been dismissed as a Hoaxer for not producing sufficient evidence to link him to bitcoin blockchain.
There are many other people thought to have invented bitcoin blockchain but have denied it. It is possible that the technology was invented by a group of people.