(AP) — Billionaire Warren Buffett turns 83 on Friday, and he’s not saying whether he’s planning to surprise his Berkshire Hathaway shareholders with a big acquisition to celebrate.

On his last birthday, Buffett announced plans to significantly increase the amount of Berkshire stock he will give to each of his three children’s charitable foundations.

In most years, the investor prefers to celebrate with a day at the office reading business reports and hunting for deals. Buffett has said he enjoys running Berkshire too much to consider retiring.

Buffett has had a relatively quiet summer since Berkshire acquired half of the ketchup maker H.J. Heinz Co. in June. Berkshire spent $12.25 billion on the Heinz deal, but still had $35.7 billion on hand at the end of June.