Take context from the input text and decide on the accurate relationship between 'Berkshire Hathaway' and 'Phillips 66' from the options provided.
Options: owner of, owned by, distributed by, subsidiary

(Reuters) - Warren Buffett's Berkshire Hathaway Inc (BRKa.N) disclosed a $4.48 billion stake in oil refiner Phillips 66 (PSX.N), rebuilding a bet it had made in the energy industry before oil prices fell.
owner of