Slack-fill is the void space in packaging resulting from a difference between the volume of packaging and the volume of product. Not all slack-fill is proscribed. “Functional” slack-fill is permissible, while undisclosed nonfunctional slack-fill is often prohibited. The devil is in distinguishing between the two, and the consequences for failing to properly do so are higher than ever.
Federal, Calif. ‘Slack-Fill’ Laws Ensure Fill Of Litigation
November 18, 2015