A stock purchase agreement is a legally binding contract between shareholders and companies that outline all of the terms and conditions related to the sale of a company's stock.
This is a formal contract that enables two parties to transact shares in a business. It sets the price, quantity of shares, and date of the exchange to ensure both parties can come together to transact.
The benefits of a stock purchase agreement are that everything is well defined so both parties have a clear understanding of what to expect.