There is no legal requirement for a company to have an employee handbook in California.
The above is general legal and business analysis. It is not "legal advise" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
Public, private, large, small --every type of company can have one, or not, as they like. Most big businesses do, since it's going to be written to protect them.
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