There is no law requiring her to change her name for any purpose. As long as she is not using a name for a fraudulent purpose, she can call herself anything she wants. My wife and I have separate names for business purposes and joint for personal purposes. Never a problem in 24 years.
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Mr. Schwerin is correct. She does not even need to file a fictitious business name statement.
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Names under CA law. Very simple. She should not use a name that is a famous one. Wouldn't be prudent. For example, I would not suggest she solicit donations to her favorite charity under her magical new name of Doctor Michelle Obama. And, she should not use a name in order to commit fraud or to defraud creditors. Trying to get a credit card in Washington, DC using her magical new name of Hillary Clinton might get her a credit card, but it might eventually lead to a fraud charge if she defaults, Wouldn't be legal. Period. Hope these examples help. Much safer for her to call herself Dr. Joey Schlobotnick on alternating weekends when visiting friends at Colton's Olive Dell Ranch. Understand name tags are not needed there.
Seriously, she should have no problems, assuming her maiden name is not Alberta Einstein or Madam Curie. Many professional women do precisely what she's contemplating. Some of them are California lawyers who have degrees, licenses, certifications, etc. Some women who are not licensed professionals nonetheless have reputations they do not want to abandon upon marriage. Entertainers, for instance. Writers. Professional athletes. Politicians. The list goes on.
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