On Jul. 15, 1998, Aptein, founded by Glenn Kawasaki in Seattle, was acquired by Cambridge Antibody Technology (CAT) in the UK. Dr. Kawasaki is the inventor of ribosome display and he founded Aptein in 1989 for cell-free engineering of proteins and peptides.

CAT purchased the issued share capital and outstanding share options and warrants of Aptein for a total consideration of up to $11 million satisfied by the issue of up to 2.366 million CAT shares. $6 million of the consideration was satisfied by the issue of 1.290 million CAT shares on closing.