Order and supplemental and resettled order affirmed insofar as appealed from, without costs or disbursements.
Special Term did not abuse its discretion in allowing defendants to amend their answer (see, Fahey v County of Ontario, 44 N.Y.2d 934, 935; Castro v Boulevard Hosp., 106 A.D.2d 539, 540).
The management agreement which plaintiffs seek to enforce through their sixth and seventh causes of action is violative of the laws of this State prohibiting fee-splitting arrangements (see, Matter of Bell v Board of Regents, 295 N.Y. 101, 111, reh denied 295 N.Y. 821; United Calendar Mfg. Corp. v Huang, 94 A.D.2d 176, 180; Education Law § 6509-a; 8 NYCRR 29.1 [b] [4]). The fact that the agreement was executed in 1973, prior to the effective dates of Education Law § 6509-a and 8 Educ. NYCRR 29.1 (b) (4) does not help to sustain plaintiffs' claim because fee splitting was proscribed long before 1973 (see, e.g., Matter of Bell v Board of Regents, supra; State of New York v Abortion Information Agency, 37 A.D.2d 142, 144, affd 30 N.Y.2d 779; Matter of Popper v Board of Regents, 26 A.D.2d 871; Radnay v Schor, 41 Misc.2d 789, 790; cf. United Calendar Mfg. Corp. v Huang, supra). "It has never been necessary * * * to define with particularity acts which constitute unprofessional conduct" (Matter of Bell v Board of Regents, supra, p. 108; Matter of Irwin v Board of Regents, 33 A.D.2d 581, 582, affd 27 N.Y.2d 292).
We agree with Special Term's finding that plaintiffs, being nonprofessionals, were less culpable and therefore not in pari delicto with defendants (see, Smith v Pope, 72 A.D.2d 913).
We have examined the parties' remaining contentions and find them to be without merit. Brown, J.P., Rubin, Lawrence and Kooper, JJ., concur.