Lone Star came under fire after the Texas-OU game when dozens of football fans returned to find their cars had been towed.
A city investigation found Lone Star Auto Services received 24 violations of the Dallas City Code.
Investigators with the city also found an additional 40 complaints of violations related to incidents at the State Fair on October 11.
Among the violations, the tow company removed cars from areas where signs were not posted at least 24 hours before they were towed.
The state's Department of Licensing and Attorney General's Consumer Protection Divsion are also investigating claims Lone Star's actions were illegal.
Lone Star later agreed to reimburse more than two dozen people whose cars were towed during the football game, but the company said it had orders to tow vehicles from the property.