concurs in part and dissents in part in the following memorandum. Casey, J. (concurring in part and dissenting in part). While I agree with the majority that the question of whether a joint venture existed was not litigated before the board, in my view Special Term erred with regard to the third-party defendant Service Scaffold, Inc., and the order should be modified accordingly. The joint venture issue is relevant only insofar as it relates to the affirmative defense created by section 11 of the Workers’ Compensation Law, and its relevance here arises due to the board’s finding *929that defendants Howard Ingber, Brian Ingber and Rose Ingber, doing business as H.R.B. Ingber, were plaintiff’s employers. Standing alone, such a determination should not preclude the remaining defendants from asserting that they, too, were plaintiff’s employers on the theory that they were joint venturers with H.R.B. Ingber. However, in a decision dated May 6, 1975 the board had originally found third-party defendant Service Scaffold, Inc., to be plaintiff’s employer. Thereafter, apparently at the request of Service Scaffold, Inc., a new hearing was held, and the board rescinded its May 6, 1975 decision and ruled that H.R.B. Ingber was plaintiff’s employer. Implicit in this decision is the finding that Service Scaffold, Inc., was not plaintiff’s employer. Accordingly, since Service Scaffold, Inc., has been determined not to be plaintiff’s employer, the joint venture issue as to it is irrelevant and plaintiff’s motion to strike the affirmative defense of Service Scaffold, Inc., should have been granted.