IBM Executive VP Steven A. (Steve) Mills, a 40-year IBM veteran and a key player on the IBM management team for the past two decades, retired on December 31, according to several published reports. The announcement was cited as the cause of a sharp drop in IBM shares on the New York Stock Exchange earlier today, but the share price recovered to finish the day nearly unchanged.

Mills, 64, joined IBM in 1973 and was closely associated with IBM’s software organization since its inception in 1995. In January 2015 he was named executive vice president, IBM Software and Systems, where he took on responsibility for directing approximately 110,000 employees, spanning development, manufacturing, sales, marketing and support.

With the addition of Systems, he was responsible for IBM products that contributed $40 billion of IBM’s revenue and provide critical business integration infrastructure used by more than 100,000 companies worldwide. Mills also oversaw more than 30 IBM software acquisitions, including SPSS Inc., Cognos Corp., Candle Corp., DataMirror Corp. and FileNet Corp.

Mills was a four-time guest on theCUBE. His appearances were characterized by a sometime rapier wit and a no-holds barred attitude toward competitors. The video below was recorded at the IBM Pulse conference in February, 2014.