A joint marketing agreement is a legal contract that governs the relationship between two or more companies to collaborate in advertising, promotion and sales. Joint marketing agreements are contracts that allow companies to market for each other and share audiences.Learn how to manage these agreements. Co-Marketing Agreement sample contracts and agreements. This joint marketing agreement template will help establish a formal relationship between two parties who wish to engage in joint marketing efforts. Visit the contracting disclosure website and complete the form. Log into the contracting disclosure website. A joint marketing agreement or similar agreement is necessary in order to set forth the rules of the road for the parties' relationship. In the event that two Businesses apply jointly, the Contribution Agreement shall include: i. A schedule of Payments, and ii.