Why you can write your name any way you want.
Last week I wrote about omitting the comma before "Jr." in a name, and I got messages from a few juniors who objected to the rule. They said they've always written their names with a comma, and they aren't going to change now.
My sources for omitting the comma are the Chicago Manual of Style, the Associated Press Stylebook, and Garner's Modern American Usage--I don't just make this stuff up. However, Chicago also states that writers should make a reasonable effort to spell a name the way a person spells it himself or herself, and I presume that also applies to punctuation. In other words, you're free to insist on the comma before "Jr." in your own name.
If you're ever interviewed for a newspaper, magazine, or website, and you're a junior who feels strongly about having the comma in your name, you should probably mention it to the reporter. If the musician Prince can be O(+>, you can certainly have your comma.
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