John L. Castello

JOHN L. (JACK) CASTELLO is Chairman, President and Chief
Executive Officer of XOMA Ltd. He joined XOMA in 1992. From 1986
to 1991 he was with the Ares-Serono Group, first as President of
the Worldwide Diagnostics Division and then as President and
Chief Operating Officer of the worldwide Group. During his tenure
as President, the Group’s actual sales increased from $300
million to $750 million. From 1977 to 1986, he was with Amersham
International, rising to the post of Chief Executive of the
worldwide Medical Divisions. Previously, he worked for Abbott
Laboratories and General Foods in a progression of management
positions. Mr. Castello holds a BS degree in
Mechanical/Industrial Engineering from Notre Dame University.