2009 California Food and Agricultural Code - Section 39431-39432 :: Article 4. Misrepresentation

39431.  A person shall not sell or take orders for the future
delivery of any margarine, dairy spread, or spread under the name of
butter, or under the pretense that the substance is butter.

39432.  A person shall not, in connection or association with the
sale or advertisement of any margarine, dairy spread, or spread
represent or suggest by any means whatsoever that the substance is a
dairy product. Nothing contained in this section shall, however,
prevent an accurate and full statement of all of the ingredients
which are contained in such substance.