In this guide, we will explain what buying out a business partner means, how to prepare to buy out a business partner, and more. Sell agreement is a contract made between shareholders that limits a shareholder's actions in the sale or transfer of shares if they leave the company.A buy sell agreement is a legally binding agreement between business partners that explains the process of events after a partner leaves the business. As a transactional lender, Celtic Bank can help you secure financing to buy out a partner without interfering with your existing business lender. We've created a detailed guide on effectively ending a business partnership. We've included our own experiences as well as our expert tips and tricks.