Based on these facts, the joint venture should be treated as a partnership and treated accordingly. Under Illinois law, any two or more persons who operate an unincorporated business together (that is, who “carry on as co-owners a business for profit”) are automatically considered to be a partnership, even without a written agreement or a filing with the Secretary of State. 805 ILCS 206/202(a).  

The joint venture/partnership must obtain a unique Employer Identification Number (EIN) (see Understanding Your EIN, IRS Publication 1635 (printed page 6, page 8 of the PDF file)), and the CIP regulations require you to collect an EIN from every business customer, as well as its name and address (a principal place of business, local office or other physical location for a business account).  31 CFR 1020.220(a)(2).

In addition, the FFIEC’s BSA/AML Examination Manual recommends that you obtain “articles of incorporation, a corporate resolution by the directors authorizing the opening of the account, or the appointment of a person to act as a signatory for the entity on the account” for all business accounts. Business Entities (Domestic and Foreign)—Overview. In this case, since the joint venture will not be incorporating as a business entity, we advise that you obtain a written appointment by all of the owners of the joint venture that specifies the person or persons who will be an authorized signer for the account.