66 Pa.C.S. § 512

The commission may, as to motor carriers, prescribe, by regulation or order, such requirements as it may deem necessary for the protection of persons or property of their patrons and the public, including the filing of surety bonds, the carrying of insurance, or the qualifications and conditions under which such carriers may act as self-insurers with respect to such matters. All motor carriers of passengers, whose current liquid assets do not exceed their current liabilities by at least $100,000, shall cover each and every vehicle, transporting such passengers, with a public liability insurance policy or a surety bond issued by an insurance carrier or a bonding company authorized to do business in this Commonwealth, in such amounts as the commission may prescribe, but not less than $5,000 for one and $10,000 for more than one person injured in any one accident.