Fighter's Familiar BAB

[Wind Chime]

Would an Eldritch Guardian's familiar have full BAB (like his own) or half BAB (like an equal level wizard would have?)

[Issac Daneil]

A familiar's BAB is always equal to the master's BAB, unless stated otherwise (Like the Spirit Binder)

[Jeff Merola]

Full BAB. A familiar uses its master's full BAB, even including any levels in classes he has that don't grant familiars.

[lemeres]

The familiar gets most of your base stats other than HP. So BAB, base saves, skills, etc.

This is how all familiars work. It would be the same even if the fighter just took a dip into wizard- her would use his whole BAB (not continuing wizard would just limit things like natural armor scaling)