Cal. Rev. & Tax. Code § 30186

On or before the 25th day of each month, the common carriers and authorized persons specified in Section 30104 shall file, using electronic media, with the department a report of the sales of cigarettes or tobacco products made by them on the facilities of the carriers in California in the preceding calendar month in that detail as the department may prescribe and in the form as prescribed by the department, submitting with the report the amount of the tax due under Section 30104. Reports shall be authenticated in a form or pursuant to methods as may be prescribed by the department.