Exxon Mobil Corp. named IBM chief executive officer Samuel Palmisano yesterday as presiding director in a bid to strengthen corporate governance, an area where investors have pressed the U.S. oil company for change. Mr. Palmisano, in the new role, will call and chair executive sessions of the non-employee directors, and will chair all board meetings in the absence of the chairman, Exxon said. The IBM chief has been on the Exxon board since 2006. Earlier this year, dissident shareholders including members of the Rockefeller family called on Exxon to change its governance policies, including splitting Rex Tillerson's job as chairman and CEO. Mr. Palmisano's appointment is effective immediately, Exxon said. As part of the changes approved by Exxon's board, the presiding director is chosen by non-employee directors and is expected to serve a minimum term of two years. XOM (NYSE) rose $3.20 (U.S.) to $77.49.