Feb 10 (Reuters) - Berkshire Hathaway Inc has bought an additional $1 billion of stock in Phillips 66 this year, and now owns roughly 14.1 percent of the oil refiner.

The conglomerate run by Warren Buffett has purchased about 12.98 million Phillips 66 shares this year, including nearly 2.18 million shares in February, according to regulatory filings through Tuesday night.

Berkshire now owns 74.47 million Phillips 66 shares worth about $5.62 billion, based on Tuesday's market close of $75.44. Berkshire has paid just over $77 per share for its added stake.

Phillips 66 is Berkshire's sixth-largest common stock holding, according to regulatory filings.

The larger holdings are American Express Co, Coca-Cola Co, IBM Corp, Kraft Heinz Co and Wells Fargo & Co, the filings show.

Berkshire also owns close to 90 businesses in industries including energy, food, insurance, manufacturing, railroads and retail. Last month, the Omaha, Nebraska-based company paid about $32 billion for industrial parts maker Precision Castparts Corp. (Reporting by Jonathan Stempel in New York; Editing by Frances Kerry)