The Illinois Assignment of Oil and Gas Lease (All Assignor's Undivided Interest in Nonproducing Lease — Short Form) is a legal document that allows an assignor, who holds a nonproducing oil and gas lease in Illinois, to transfer their entire undivided interest in the lease to an assignee. This assignment is generally used when the assignor no longer wishes to retain their rights and wants to transfer their interest to another party. Keywords: Illinois, Assignment of Oil and Gas Lease, undivided interest, nonproducing lease, short form, transfer, assignor, assignee. There are no specific variations or different types mentioned for the Illinois Assignment of Oil and Gas Lease (All Assignor's Undivided Interest in Nonproducing Lease — Short Form). However, it is important to note that there may be other types of assignments or lease forms in Illinois specifically designed for different purposes or scenarios, such as assignments for producing leases or longer lease forms with additional provisions. It is crucial to consult with an attorney or legal professional to ensure the correct form is used for a specific situation and that all necessary terms and provisions are included in the assignment document. Failure to use the appropriate form or omitting important clauses may result in legal complications or the invalidation of the assignment.