Wiktionary
which've
contraction (context neologism English) (contraction of which have English)
Usage examples of "which've".
But it's our standards which've got to succeed, because we're cursed with being unique.
It's about two Assemblymen—actually a man and a woman—being suspended by the Authority pending an investigation into their part in activities which've been deemed by the Authority to be outside the bounds of the Assembly's proper sphere of concern.