A hedge fund run by legendary investor Bill Miller is now half invested in bitcoin.

"It's just about 50 percent right now," Miller said regarding his MVP 1 fund on the WealthTrack podcast with Consuelo Mack released last week.

Miller founded Miller Value Partners in 2016 after a 35-year career at Legg Mason, where he managed a fund that beat the S&P 500 for 15 straight years through 2005. He's known for concentrated bets, but nothing on the scale of half a fund. Miller said on the podcast that in the 1990s, his fund at one point had 20 percent in AOL, close to 20 percent in Dell and 10 percent in Fannie Mae.

Bitcoin 12-month performance

Source: CoinDesk

In late October, The Wall Street Journal reported that Miller's fund had nearly a third in bitcoin and about $154 million in assets under management. At the time, the digital currency was trading near $6,000. Bitcoin has since more than tripled to above $19,000 as investor interest has grown.

Miller's overall firm manages $2.2 billion, including separate accounts for high net worth individuals and mutual funds.

"What we're studying is ways in which we can mitigate risk to the overall fund and the portfolio," he said on the podcast. "It won't be 50 percent of the fund for that much longer, which does not mean necessarily that we're going to be selling it."

The fund hasn't bought other cryptocurrencies yet, Miller said, and plans to stay focused on bitcoin. "Most of those cryptocurrencies, if monetary history is any guide, will be worthless."

However, he said his son — a portfolio manager at Miller Value Partners — has been pitching him on a coin that is holding an initial coin offering in about month which is the "first one that he's looked at that he thinks is investible."

Miller said on the podcast that he bought bitcoin in 2014 and 2015 for an average price of $350 each, with some below $200 and some above $500. Forbes reported in July that Miller put 1 percent of his net worth into bitcoin in 2014.

Listen to the WealthTrack podcast here.