There are no regulations on the what price you can charge on a product in relationship to the package size. However, there is a regulation on food package size in relation to net contents. The Food and Drug Administration (FDA) issued a final regulation on "slack-fill" on December 6, 1993 (58 Fed. Reg.64136), which became effective on January 5, 1994. "Slack-fill" is defined as the difference between the actual capacity of a container and the volume of product contained therein, and "nonfunctional slack-fill" is defined as the empty space in a package that is filled to substantially less than its capacity. FDA prohibits nonfunctional slack-fill unless: (1) it performs an appropriate function, such as protecting the contents of the container; (2) it is necessary because the machines used for enclosing the contents in the package require it; (3) it is the result of "normal product settling;" (4) the package performs a specific function that is inherent to the nature of the food and is clearly labeled; (5) the product is a food packaged in a reusable container where the container is part of the presentation of the food, e.g. , a gift product; or (6) the manufacturer cannot increase the level of fill or reduce the size of the package (e.g., where a minimum package size is necessary to accommodate required food labeling, discourage pilfering, facilitate handling, or accommodate tamper-resistant devices).