The Collaborative International Dictionary of English v.0.48:

invalidating \invalidating\ adj.
   tending to invalidate or prove false.

   Syn: disconfirming.
        [WordNet 1.5 +PJC]

The Collaborative International Dictionary of English v.0.48:

Invalidate \In*val"i*date\, v. t. [imp. & p. p. Invalidated;
   p. pr. & vb. n. Invalidating.] [From Invalid null.]
   To render invalid; to weaken or lessen the force of; to
   destroy the authority of; to render of no force or effect; to
   overthrow; as, to invalidate an agreement or argument.
   [1913 Webster]

WordNet (r) 3.0 (2006):

invalidating
    adj 1: establishing as invalid or untrue [syn: disconfirming,
           invalidating]