California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 41063
# (a)
Any return, declaration, statement, or other document required to be made under this part that is filed using electronic media shall be filed and authenticated pursuant to any method or form the department may prescribe.
# (b)
Notwithstanding any other law, any return, declaration, statement, or other document otherwise required to be signed that is filed by the taxpayer using electronic media in a form as required by the department shall be deemed to be a signed, valid original document, including upon reproduction to paper form by the department.
# (c)
Electronic media includes, but is not limited to, computer modem, magnetic media, optical disk, facsimile machine, or telephone.
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