Ackermann's departure from Shell is the latest retreat from high-profile corporate positions for the former Deutsche Bank (>> Deutsche Bank AG) chief executive.
He stepped down from the supervisory board of German engineering conglomerate Siemens (>> Siemens AG) in September, two weeks after quitting as chairman of Zurich Insurance (>> Zurich Insurance Group Ltd), following the suicide of the chief financial officer.
Shell's annual meeting is scheduled for May 20. The company is holding a management day on March 13, when it will attempt to win round investors after a major profit warning in January.
(Reporting by Sarah Young, Editing by Paul Sandle)