Warren Buffett’s Berkshire Hathaway has spent another $54 million to purchase Sirius XM stock, giving it a stake of more than 35% in the satellite-radio company.

Warren Buffett’s Berkshire Hathaway (BRK.A) (BRK.B) has recently increased its stake in Sirius XM Holdings Inc. (SIRI), now owning over 35% of

Berkshire Hathaway doesn't have any major announcements planned for Jan. 30, but its top holding, Apple, does. History doesn't give investors a compelling reason to expect Berkshire stock to jump much if Apple's stock soars.