What does GUB stand for?

Generalized Upper Bounding - Computer science

Government Union of Burma

Greatest Upper Bound - Computer science

Guajajara - Language symbol (ETLW)

Guerrero Negro - Mexico - Airport symbol

Gulfmaster Yacht Inc., Davie, FL - Manufacturer code for watercraft hull identification number (USCG)

Law School Library, University of Georgia, Athens, GA - OCLC symbol (OCLC)