An asset purchase agreement (APA) is a written legal document that formalizes purchasing a business or substantial commercial asset. An asset purchase agreement is the legal document that will govern the transfer of ownership of a business's assets from the seller to the buyer.The letter of intent and the Asset Purchase Agreement should identify the assets and the purchase price. An Asset Purchase Agreement is a legally binding contract between a buyer and a seller that details the terms and conditions of the sale of a business's assets. When a client is considering purchasing all or some assets of another company, we work with them to get an understanding of what it is they are buying. Purchasing A Business Or Business Assets. An asset purchase contract defines the assets and liabilities to be sold when one company purchases another. Assets included with the purchase agreement: The business's assets should be listed in the purchase agreement, specifying what is included with the sale.