Participation accounts are the only type of company or internal community known by commercial law, which generally lack legal personality. It is an associative formula between individual or social entrepreneurs that makes it possible for one of them (the participant) to participate in the company of the other (manager), with both remaining as a result of the success or failure of the latter. Its status as a company leaves no doubt: the common goal pursued is to obtain profits through the exploitation of the manager's business and both parties contribute to its achievement. The participation account is a commercial type due to the subjects.

Indeed, from the usual definition contained in commercial regulations (especially Commercial Codes) it follows that joint accounts are commercial and, therefore, subject to the special regulations of this area, provided that they are established between merchants. There is, however, no difficulty in resorting to them in the traffic of civil law, creating an analogous form, using contractual freedom") or using the same accounts to enable a non-merchant third party to become interested in the activity of a liberal professional, for example.[1]​.

Commercial legislation usually follows the principle of freedom of form in the constitution of joint accounts. For the rest, the parties enjoy the greatest freedom to establish the conditions of the relationship. In the internal sphere, property relations are based on the duty to contribute. The participant is obliged to deliver to the manager or owner of the business the agreed capital "Capital (economy)", which may consist of money or goods, and what is contributed becomes the domain of the manager, unless otherwise stated in the contract.

Commercial regulations do not usually regulate the causes of termination of accounts, but given their corporate nature, the rules on dissolution of companies will apply. As an example, the following may be indicated: mutual dissent, expiration of the time indicated in the contract, death or incapacity of the managing partner, if there is no agreement to continue the account with his heirs, bankruptcy of the managing partner due to his disqualification from carrying out the business subsequent to it, etc. The termination of the legal relationship of joint accounts will imply, in any case, its liquidation in accordance with what was agreed in the contract.

In general, joint accounts are regulated by commercial law. Thus, as an example, we can quote: