A Standard Document typically used in transactions for the purchase and sale of commercial real estate that includes third party leases. The seller assigns its interest, as the landlord, under the leases encumbering the real property being sold. The purchaser assumes all of the seller's interest in the leases as of the closing date. This Assignment and Assumption of Leases favors the purchaser assignee because the seller assignor provides representations and warranties. This Standard Document has integrated notes with important explanatory and drafting tips.