General counsel Robert Weber, the man who added “faster” and “smarter” to IBM’s classic THINK motto in the legal department, is leaving his post Jan. 1 after eight years in the job.

International Business Machines Corp., better known by its initials IBM, announced early this week that Weber, who turns 64 this month, would serve as a senior adviser to the company until he retires later in 2015. The sudden news came in a Form 8-K filing with the U.S. Securities and Exchange Commission, and IBM didn’t immediately respond to requests for interviews.