In July 2019, IBM Corporation acquired all of the outstanding stock of Red Hat Software. Cash paid for outstanding Red Hat stock totaled $177,485 million. In addition, stock-based compensation awards attributable to pre-combination services had a fair value of $887 million, and stock issued to holders of vested performance share units were valued at $536 million. Acquisition-related legal and advisory fees of $964 million were paid in cash. Compensation related to employee retention plans for the period following the acquisition, paid in cash in 2019, totaled $1,173 million. An estimated $944 million associated with these retention plans remains to be paid in future years. Red Hats balance sheet at the date of acquisition, plus fair value information, are as follows (in millions)