Tyler and Cameron Winklevoss have revealed that they have personally invested in ether, the digital asset that powers the Ethereum blockchain.

The announcement follows on the heels of news the New York State Department of Financial Services (NYDFS) said it will allow the brothers to add an Ethereum trading product to their digital currency exchange, Gemini.

In interview, Tyler Winklevoss said he wanted to make clear their investment as part of the disclosure surrounding next week's launch.

Winklevoss told CoinDesk:

Winklevoss said he and his brother began acquiring ether earlier this year. Though they aren't currently sharing the exact amount they’ve purchased, Winklevoss said it was a "material" number.

The brothers entrance into the Ethereum market is notable as in April 2013 it was widely reported that they owned 1% of all bitcoins in circulation. The number was the estimated to be 108,000 BTC, which at today’s value would be worth about $48.6m.

The digital currency first came to the brothers' attention last year as it rose in popularity among members of the digital currency community. Then, customers of the Gemini exchange began to ask for the asset to be added as an option, Winklevoss said.

During their exploration of Ethereum as an asset class, the brothers were attracted to what Tyler described as its distinguishing attributes. Namely, that it includes a Turing-complete computer language and that it can be used as fuel for performing different smart contract-related tasks.

Though Tyler Winklevoss said he and his brother still believe in the value of bitcoin as an asset class in its own right, these distinctions inspired them to make their own investment and open up the exchange to help others do the same.

"We looked at the people in both communities and the people putting time into it," said Tyler Winklevoss, adding:

But, there's more at play here than just the addition of a new investment tool.

At press time, Gemini is currently trading about 811 BTC per day (roughly $360k), a figure that's below other regulated US competitors itBit and CoinBase, which are trading about 3,000 BTC and 5,000 BTC, respectively.

Still, Tyler Winklevoss told CoinDesk the company’s trading volumes are in alignment with their expected growth and distinguished his company from some competitors.

He told CoinDesk:

Ether trading is scheduled to begin on Gemini at 9:30am EST on Monday.

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