Bitcoin is rallying and can no longer be ignored, said Brian Kelly, founder and CEO of BKCM LLC, an investment firm focused on digital currencies.

"It's a serious market," Kelly said from Hoover Institution's annual Monetary Policy Conference at Stanford University on Friday.

"When I would go to events like this in years past, you would kind of dismiss bitcoin," Kelly said on "Fast Money." "But it's been brought up several times at this conference and taken quite seriously. And I think you have to with a market cap at half a trillion dollars."

The cryptocurrency reached $9,700 around 5:15 p.m. ET Friday. While significantly lower than its mid-December highs around $19,700, the coin continues to regain losses from lows of around $6,000 earlier this year.

Kelly credits Goldman Sachs and its plans to open the first bitcoin trading firm of any Wall Street bank for pushing the demand higher.

"Goldman made a big move into the cryptocurrency space," Kelly said. "They are definitely the leaders among the institutions in the space."

Regulatory clarity is also pushing the coin's value higher.

"One thing that is interesting is that bitcoin is clearly a currency," Kelly said. "Almost everyone I've talked to, and people here at this event, are talking about bitcoin as a currency, not a security."

Finally, Kelly said Blockchain Week New York City, bitcoin's biggest event, is coming up next week, helping to generate more buzz around the coin.

"Essentially, everyone from the world will be descending upon New York to talk about cryptocurrency," he said.