The DMV rejects license plates regularly, and there seem to be a lot of people intentionally trying to slip potentially offensive terms into their vanity plates. California has a reputation that makes its DMV likely to be the most restrictive when it comes to what might be rejected. There’s a great twitter account named @ca-dmv-bot posting rejections and responses regularly here. Below are several observations that summarize common reasons for the California DMV’s many rejections.

• Gang references: Red, 13, 14, 88, Hefe
• OG and even just G by itself
• 88 and 18 are denied as a reference to Hitler
• 50, pig and blue are frequently blocked as references to police
• Anything resembling kill, murder; examples include kyl or mrdr
• Any perceived reference to a weapon or drug (even the letter J)
• Any numbers that may translated to an area code
• Anything perceived as a potential sexual terms or connotations such as cat, kitty, monkey, toy, 69, D, prn, taco
• Anything perceived as potentially hostile, including just “u” or “ur”