225 ILCS 725/23.8
No order of the Department providing for unit operations shall become effective unless and until the plan of unitization has been approved in writing by those persons who, under the order, will be required to pay at least 51% of the unit expense, and also by the persons owning at least 51% of the unit production or proceeds thereof that will be credited to interests which are free of unit expense, including but not limited to, royalties, overriding royalties, carried interests, net profit interests, and production payments, and the Director has made such a finding, either in the order providing for unit operations or in a supplemental order, that the plan of unitization has been so approved; provided, however, that if any person is obligated to pay 51% or more, but less than 100% of the unit expense, the approval of that person and at least one other such person shall be required; and if one person entitled to production or proceeds thereof will be credited to interests which are free of unit expense, owns 51% or more, but less than 100%, the approval of that person and at least one other such person shall be required. If the plan of unitization has not been so approved at the time the order providing for unit operations is issued, the Department shall, upon petition and notice, hold such supplemental hearings as may be required to determine if and when the plan of unitization has been so approved and shall issue a supplemental order evidencing such approval. If the requisite number of persons and the requisite percentage of interests in the unit area do not approve the plan of unitization within a period of 6 months from the date on which the order providing for unit operations is made, such order shall be revoked by the Department unless for good cause shown the Department extends said time for an additional period of time not to exceed one year.
225 ILCS 725/23.8