A long form of assignment and assumption of lease agreement where the tenant assigns its leasehold interest in a lease to a third party assuming the tenant's lease obligations. This Standard Document is for use with a commercial lease (such as for retail or office space) of premises located on Illinois real property and contains representations, warranties, and indemnities by the assigning tenant and the third-party assignee. This Standard Document has integrated notes with important explanations and drafting and negotiating tips for both the assignor and the assignee.