An asset purchase agreement (APA) is an agreement between a buyer and a seller that finalizes terms and conditions related to the purchase and sale of a company's assets. It's important to note in an APA transaction, it is not necessary for the buyer to purchase all of the assets of the company. In fact, it's common for a buyer to exclude certain assets in an APA. Provisions of an APA may include payment of purchase price, monthly installments, liens and encumbrances on the assets, condition precedent for the closing, etc. An APA differs from a stock purchase agreement (SPA) where company shares, title to assets, and title to liabilities are also sold. In an APA, the buyer must select specific assets and avoid redundant assets. These assets are itemized in a schedule to the APA. The buyer in a SPA is purchasing shares of the company. In this case, itemization is not necessary due to transfer of company's ownership occurs as is. The APA is the legal mechanism for executing a corporate merger or acquisition. The oil and gas industry does not distinguish between an asset and stock purchase in naming its related purchase agreement. In this industry, whether purchasing assets or stock, the definitive agreement is referred to as the purchase and sale agreement (PSA).