California Code, Labor Code - LAB § 3550

(a) Every employer subject to the compensation provisions of this division shall post and keep posted in a conspicuous location frequented by employees, and where the notice may be easily read by employees during the hours of the workday, a notice that states the name of the current compensation insurance carrier of the employer, or when appropriate, that the employer is self-insured, and who is responsible for claims adjustment.

(b) Failure to keep any notice required by this section conspicuously posted shall constitute a misdemeanor, and shall be prima facie evidence of noninsurance.

(c) This section shall not apply with respect to the employment of employees as defined in subdivision (d) of Section 3351.

(d) The form and content of the notice required by this section shall be prescribed by the administrative director, after consultation with the Commission on Health and Safety and Workers' Compensation, and shall advise employees that all injuries should be reported to their employer.  The notice shall be easily understandable.  It shall be posted in both English and Spanish where there are Spanish-speaking employees.  The notice shall include the following information:

(e) Failure of an employer to provide the notice required by this section shall automatically permit the employee to be treated by their personal physician with respect to an injury occurring during that failure.

(f) The form and content of the notice required to be posted by this section shall be made available to self-insured employers and insurers by the administrative director.  Insurers shall provide this notice to each of their policyholders, with advice concerning the requirements of this section and the penalties for a failure to post this notice.