Q: Two out of three partners would like to employ an additional worker. Can they force their majority opinion on the third partner?
A: If the initial partnership agreement specified following the majority, the terms are binding. This also applies if there is a clear common practice to follow the majority.
In the absence of specific terms or a clear common practice to follow the majority, the minority can prevent making decisions against the standard practice of the trade (Pischei Choshen, Shutfim 2:). On issues where there is no standard practice, such as adding additional workers, the majority rules, since it is impossible to come to unanimous agreement on every issue and they became partners with this intention (Igros Moshe, C.M. 2:23).
Nonetheless, the majority should give the third partner an opportunity to voice his opinion and reasoning. Furthermore, the majority cannot make decisions that benefit them at the expense of the minority, since the latter has a vested interest (nog’im badavar) — (Pischei Teshuvah, C.M. 163:1).