An oval surrounding the 'E' would have indicated that it belonged to a county within California while a diamond would have indicated that it belonged to the state itself.ġ930 - Passenger vehicle / Embossed steel The square surrounding the 'E' indicated that the vehicle belonged to a city. The 'E' signifies that this car was owned by a branch of government and thus exempt from taxes. The year 1929 also marked an increase in the size of California license plates and the introduction of a new numbering system beginning with the prefix '1A'. In 1929 California and New York adopted an orange and black license plate color scheme after a federal study determined that such a combination was the most visible both day and night. The letters 'PC' stand for 'pneumatic commercial', which denoted that a vehicle was intended for business use and had pneumatic tires instead of solid tires, which tended to damage roads and were taxed at a much higher rate as a result.ġ929 (top) - Passenger vehicle / Embossed steelġ929 (bottom) - Official city vehicle / Embossed steel A diamond around the 'E' denoted a state vehicle, an oval denoted a county vehicle, and a square denoted a city vehicle. The letter 'E', for example, denoted that a vehicle was owned by a government and thus exempt from taxes. Another major change was the incorporation of letter codes to indicate a type of vehicle or driver. An orange and black color scheme was also adopted after a federal study determined that such a combination was the easiest to see both day and night. The year also marked the introduction of a larger, more readable plate size and a new numbering system beginning with the prefix '1A'.

Beginning in 1929 the Norris Manufacturing Company in Los Angeles began producing California's license plates.

California license plate dimensions