Business transactions can be conducted through agents; but if the agent does not fulfill his instructions the transaction is invalid. Legal actions can be conducted only by agents who are authorized in writing. A partner can take legal action on behalf of the entire partnership.^a

Partnerships are formed only by an act of mutual sale. One partner can prevent another from conducting a transaction that does not conform to the wishes of the partnership; and if a partner conducts such a transaction he must bear any resulting loss himself. If a partner dies the partnership is dissolved.^b

An agent (or guardian) or partner who transacts business is rabbinically required to take an oath that his accounts are correct if they are questioned; and similarly if there is disagreement about the agent's instructions or the terms of the partnership.^c