Cal. Bus. & Prof. Code § 12606
(b) No container shall be made, formed, or filled as to be misleading. A container that does not allow the consumer to fully view its contents shall be considered to be filled as to be misleading if it contains nonfunctional slack fill. Slack fill is the difference between the actual capacity of a container and the volume of product contained therein. Nonfunctional slack fill is the empty space in a package that is filled to substantially less than its capacity for reasons other than any one or more of the following:
(8) One or more of the following: