Originally Posted by rtmf

GGUs are freely transferable. You simply give the beneficiary the code(s).

The much harder part is finding a flight on which to use a GGU. There's lots of threads on that here, so you can do your own research. The gist is that you need to search by MVP Gold Guest in the upgrade fare type selection (left column of search results). Then look for F boxes that are colored blue, not white. Realistically, an expert flyer subscription will probably be needed if you really want to get good value.