Billionaire Warren Buffett's company has taken a new stake in Canadian firm Suncor Energy and trimmed its huge Apple stake.

Berkshire Hathaway Inc. filed a quarterly update on holdings with the Securities and Exchange Commission on Thursday.

The Omaha, Nebraska-based company said it owned 10.76 million Suncor shares at the end of last year. But these quarterly filings don't make clear who made all the investments.

Berkshire said it sold nearly 3 million Apple shares but it still held 249.6 million shares of the iPhone maker.

Investors follow what Berkshire buys and sells closely because of Buffett's successful track record. Berkshire officials don't generally comment on these quarterly filings.

Berkshire also sold the 41.4 million Oracle shares it disclosed last quarter and revealed owning 4.2 million shares of Red Hat.