The sanction was properly imposed against defendant's attorney for attempting to interject Judiciary Law § 487 claims against plaintiff law firm that were completely without merit in fact ( 22 NYCRR 130-1.1 [c] [1]). Defendant's affirmative defense of accord and satisfaction was properly dismissed for lack of proof. The first counterclaim alleging that plaintiff unlawfully retained a portion of the settlement proceeds of the underlying action in violation of the terms of the settlement agreement therein was properly dismissed because Plaintiff's right under Judiciary Law § 475 to retain the settlement proceeds as a lien could not be affected by the parties' settlement in the underlying action ( see, People v Keeffe, 50 NY2d 149, 156). The second counterclaim alleging defendant's payments of Plaintiff's fees under duress and Plaintiff's billing of disbursements that it did not actually incur is lacking in factual support. The remaining counterclaims, all alleging various acts of malpractice, viewed in a light most favorable to defendant, show nothing more than an error of professional judgment ( see, Stroock Stroock Lavan v Beltramini, 157 AD2d 590).