Early Bitcoin investors Cameron and Tyler Winklevoss have created their own index of the virtual currency, as they gear up to launch the first publicly traded US Bitcoin fund.
Announced in a regulatory filing Wednesday, The Winklevoss Index—Winkdex— will serve as the basis for an exchange-traded fund the twin brothers are planning for later this year.
The Winkdex will represent a "blended price" for Bitcoins based on the prices on the top three US exchanges for the currency, by volume.
Late Wednesday the price was $624.49, up 0.84 percent from late Tuesday.
The Winklevosses are tech sector venture capitalists initially famous for their claim to having had the original idea for Facebook, and have picked up tens of millions of dollars from Facebook to settle that claim.
Since then they have invested large sums in Bitcoin-related ventures as well as the currency itself.
Last year their Math-Based Asset Services filed a plan with the Securities and Exchange Commission to market the $20 million Winklevoss Bitcoin Trust, which will hold the currency as an investment.
Amid regulator wariness over Bitcoins, the trust has yet to gain formal approval.
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