The MTC has filed an amicus brief in the Vodafone case before the Supreme Court in Tennessee. The brief addresses the use of UDITPA Section 18 – equitable apportionment authority. The taxpayer argues that under the statutory cost-of-performance rule, sales of mobile telecommunications services to customers in Tennessee should not be sourced to the state. The MTC’s brief argues that the Tennessee Commissioner of Revenue properly used the authority granted under Section 18 to include those sales in the Tennessee sales factor. You can read the Commission’s brief below.