(Some companies allow former employees to keep RSUs that have met the time-based investment requirement, but not the event-based investment requirement. It is important to read the grant agreement in order to understand what happens to your RSUs when you leave the company.) A sales contract (SPA) is a legally binding contract between two parties that has entered into a transaction between a buyer and a seller. SPAs are typically used for real estate transactions, but are found in all industries. The agreement concludes the terms of the sale and is the culmination of negotiations between the buyer and seller. Many entrepreneurs feel that they will make their startup more attractive to investors by implementing an investment schedule in their shares. This is unlikely, as investment transactions with institutional investors and demanding angels depend on investors` consent to a satisfactory share restriction agreement. The agreement records all deposits made prior to negotiations and notes a part of the agreement that has already been complied with. The agreement also specifies when the final sale will take place. Practical applications in RSPAs investor-backed ventures are often used for a number of reasons, with creators and start-up shares backed by investors.