Ariz. Rev. Stat. § 28-4039
A. Motor vehicle liability insurance for a taxi, livery vehicle or limousine may be maintained as follows:
2. After the taxi, livery vehicle or limousine driver has accepted a ride request through any communication and during the time in which the taxi, livery vehicle or limousine driver is providing passenger transportation, the taxi, livery vehicle or limousine driver or the taxi, livery vehicle or limousine company shall maintain the following insurance coverage:
(b) Primary commercial uninsured motorist coverage in a minimum amount of either of the following, whichever is greater: