Order and judgment (one paper), Supreme Court, New York County (Beatrice Shainswit, J.), entered December 16, 1996, which, inter alia, granted defendants’ motion for summary judgment, declared them to be the exclusive owners of certain rights to the subject work, and dismissed plaintiff’s complaint seeking reformation, unanimously affirmed, without costs.

Plaintiff’s tender of proof of mutual mistake, even if accepted as true, does not rise to the high level required to resist a motion for summary judgment directed against a cause of action *307for reformation and based upon unambiguous contractual language (see, Chimart Assocs. v Paul, 66 NY2d 570, 574; Sagan v Sagan, 53 NY2d 635). Indeed, other than the claimed unconscionable one-sidedness of the agreement, properly-rejected by the IAS Court, we perceive no proof of mutual mistake whatsoever. Concur—Sullivan, J. P., Rosenberger, Wallach, Rubin and Tom, JJ.