Winklevoss twins cut up Bitcoin key and keep pieces in different bank vaults to protect $1.3 billion digital fortune

The Winklevoss twins say they have cut up the key to their $1.3 billion Bitcoin fortune and keep each piece in various bank vaults across America in an elaborate attempt protect their assets.

Tyler and Cameron Winklevoss, who are best known for suing Facebook's Mark Zuckerberg claiming he stole their idea for the social networking site, started buying up Bitcoin back in 2012.

They bought roughly 120,000 Bitcoins when they were less than $10 each using $11 million from the $65 million settlement they reached with Zuckerberg, the Daily Mail reports.

The two Harvard-educated were laughed at when they made the initial investment.

But they told the New York Times that they held onto their Bitcoins, and as a result have watched it soar in value recently.

"We've turned that laughter and ridicule into oxygen and wind at our back," they said.

The twins say they aren't leaving anything to chance when it comes to protecting their digital fortune.

Given it is a digital currency, Bitcoin is kept in an electronic "wallet", that can only be accessed with the matching private key or password.

Anyone who can get access to that key can then take the Bitcoin.

The Winklevosses came up with a their own system to protect their keys.

They printed off their keys and cut them up into pieces before storing them in envelopes in safe deposit boxes across the US.

If anyone happens to steal one envelope, the person would not have access to the entire private key.

The twins did try to create an ETF or an Exchange Traded Fund for the cryptocurrency, which would have opened it up to institutional investing.

That didn't happen as the US Securities and Exchange Commission rejected the application, citing the possibility of fraud.

The twins, who also competed as rowers in 2008 Beijing Olympics, still don't get close to their arch-nemesis Zuckerberg's net worth of $70 billion.