OMAHA, Neb. (AP) — Warren Buffett’s company continues selling off its BYD shares despite the positive comments he has made about the Chinese electric car maker in the past, but Berkshire Hathaway remains a major shareholder.

Berkshire said in a filing with the Hong Kong stock exchange Monday that it had sold another 1 million shares, leaving it with 13.97% of the Hong Kong-issued shares of BYD. Berkshire is only required to disclose the sales when its ownership stake decreases into another percentage point such as when it crossed below 14% here.

Buffett hasn’t explained why he’s selling the shares that he bought back in 2008, and he didn’t immediately respond to questions about it Monday. Berkshire has cut its stake from 225 million shares in August to 153.3 million shares as of this latest filing. Buffett previously praised BYD founder Wang Chanfu generously and even visited a BYD factory in China back in 2010.

Investors may have to wait for Buffett’s annual letter to shareholders next month to learn more about why he decided to reduce Berkshire’s stake in BYD although he might not even address it then if he plans to continue selling the shares. Buffett doesn’t routinely comment on his stock moves until after he is done making them.

The sales do allow Berkshire to bank some of the tremendous gains the stock has recorded as the market for electric cars took off in China. BYD said it sold 911,140 all electric vehicles and 946,239 hybrids last year.

The stake Berkshire paid $232 million for in 2008 had ballooned in value to nearly $7.7 billion by the end of 2021. Berkshire’s remaining stake is worth a little under $4 billion ($30.88 billion in Hong Kong dollars).

In addition to its roughly $300 billion portfolio of stocks, Berkshire owns more than 90 companies outright including Geico insurance, BNSF railroad and several major utilities. Berkshire also owns an eclectic mix of manufacturing and retail firms that include aviation partmaker Precision Castparts, Dairy Queen and See’s Candy.