@Mike9241
In your hypothetical, of course, because the transferor is retaining a 50% interest in the property while the other 50% is transferred to the donee (transferee). So, half of the donor's basis is essentially transferred to the donee.
However, that's not the case as laid out by @MeeshkaDiane because the transferor (aka Peter) is transferring 100% of his share (his entire interest in the property); he will have nothing left in which to have a basis.
Note: One of the problems here is we're getting multiple and varied fact patterns across two different threads so the facts are getting totally intertwined, convoluted, and altered. @MeeshkaDiane needs to keep the facts consistent and contained in one thread (moreover, the basic question was answered in the other thread).
