Bitcoin '˜creator' Craig Wright in U-turn over pledge to prove claim

The entrepreneur who has claimed to be the inventor of Bitcoin has reneged on a promise to present new 'proof' to support his case.

Australian Craig Wrights claims to be the creator of Bitcoins have been met with scepticism. Picture: PA

Craig Wright, the Australian computer scientist who claimed to be Satoshi Nakamoto, the creator of bitcoin, has backtracked on a pledge made on Tuesday to provide “extraordinary proof” of his earlier claims.

He pledged to move some of the virtual currency from one of its early address blocks, an act which many believe can only be done by the tech’s creator.

This would have addressed complaints that earlier evidence he had published online was misleading.

Yesterday Dr Wright blogged that he was “sorry”.

He maintains he really is Nakamoto, but accepts the absence of credible evidence means few are likely to believe him.

He wrote: “I believed that I could do this. I believed that I could put the years of anonymity and hiding behind me. But, as the events of this week unfolded and I prepared to publish the proof of access to the earliest keys, I broke. I do not have the courage.”

Dr Wright had attempted to prove his claim by posting what he said was a digital signature, signed using a private key that could only have been held by the real Satoshi Nakamoto.

In fact, while Dr Wright did post such a signature, it emerged it had been directly copied from a 2009-era bitcoin transaction and was not freshly created, as he had claimed.

That discrepancy led to his claims being dubbed a “scam” and “cryptographically verifiable fraud” by security researcher Dan Kaminsky.

Wright’s post added: “When the rumours began, my qualifications and character were attacked. When those allegations were proven false, new allegations have already begun. I know now that I am not strong enough for this.”

He also apologised to the two senior bitcoin figures who had backed up his claim before he went public. “I know that this weakness will cause great damage to those that have supported me, and particularly to Jon Matonis and Gavin Andresen. I can only say I’m sorry. And goodbye.”

Mr Andresen had publicly questioned Wright’s evidence a few days after it was made public, saying: “I was as surprised by the ‘proof’ as anyone, and don’t yet know exactly what is going on.”