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7 U.S. Code § 7254 - Effect on fluid milk standards in State of California

Nothing in this Act or any other provision of law shall be construed to preempt, prohibit, or otherwise limit the authority of the State of California, directly or indirectly, to establish or continue to effect any law, regulation, or requirement regarding—
the percentage of milk solids or solids not fat in fluid milk products sold at retail or marketed in the State of California; or
the labeling of such fluid milk products with regard to milk solids or solids not fat.