image copyrightGetty Images
The creator of the world wide web, Sir Tim Berners-Lee, is selling off the original code used to create the modern internet as an NFT.
NFTs are a form of unique ownership for digital-only items and do not necessarily include copyright control.
They have also been widely criticised as a money-making scheme and bad for the environment.
Some have expressed surprise at the news given that Sir Tim famously refused to patent his invention.
The sale is being handled by Sotheby's auction house, and the money made will be put towards causes chosen by Sir Tim and his wife, Sotheby's said.
Sir Tim invented the world wide web – the main modern way we use the internet – in 1989.
He proposed a way of linking together different pieces of information stored on the early internet through hyperlinks, and built the first web browser and web server.
The first web page described the idea: "Aiming to give universal access to a large universe of documents."
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Sotheby's is auctioning off a collection of four different items as a single digital NFT.
They include "the original time-stamped files" of the source code written for the project, "an animated visualisation" of that code, a letter from Sir Tim about the process, and a "digital poster" of the code created by him.
In all, the files represent nearly 10,000 lines of written code.
image copyrightGetty Imagesimage captionSir Tim photographed at MIT in March 1998
Sir Tim has never sought to make money directly from his creation, and the web remains an open standard. Cern, the research organisation Sir Tim worked for at the time, relinquished all its rights to the technology and put it in the open domain in 1993.
The value of the code is arguably in its historical significance, and the fact that this digital auction is endorsed by its creator and "digitally signed" as authentic.
Sotheby's is advertising the collection as "the only signed copy of the code for the first web browser in existence", in a manner similar to the way handwritten journals of a famous figure might be sold.
It's likely that this unusual auction will raise a hefty sum for the good causes Sir Tim and Lady Berners-Lee support. Some of the air has gone out of the NFT bubble but the web's source code is just the kind of thing likely to catch the eye of some wealthy fan of all things crypto.
Still, for the man who tweeted "this is for everyone" about the web at the London Olympics Opening Ceremony and has won huge respect for never having wanted to profit from his creation, this is a somewhat unlikely move.
There is plenty of controversy around NFTs – to some they are a brilliant innovation which means digital art and other collectibles can be monetised, to others they're little more than a giant scam which gives gullible – or publicity seeking – buyers the illusion of ownership.
But the biggest question mark is over the environmental impact of NFTs created on the Ethereum blockchain. One analyst puts the carbon footprint of a single Ethereum transaction at more than 14 times that of putting an art print in the post.
Concerns about this have seen some digital artists reject NFTs – one described them as "an ecological nightmare pyramid scheme".
We wanted to raise some of these issues with Sir Tim Berners-Lee but his office referred all questions to Sotheby's.
'It feels right'
"Why an NFT? Well, it's a natural thing to do as when you're a computer scientist and when you write code and have been for many years," said Sir Tim in press material issued by Sotheby's.
"It feels right to digitally sign my autograph on a completely digital artefact."
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And he also drew comparisons between the abstract nature of the web itself and this new idea.
"NFTs, be they artworks or a digital artefact like this, are the latest playful creations in this realm, and the most appropriate means of ownership that exists," he continued.
"They are the ideal way to package the origins behind the web."
And the auction house maintains that "the carbon footprint of this NFT is negligible" because it will pay for a carbon offset for the minting and transaction costs of the sale – though the blockchain on which the transaction lives has immense day-to-day running costs.
Sotheby's said the auction would run from 23-30 June, with an opening bid of $1,000.