Slack Fill

Slack fill is the empty space between a package’s full capacity and the amount of product inside it. For food sold in a container that does not let shoppers fully see its contents, federal rules treat the package as misleading when that space is nonfunctional.

The distinction is functional purpose. Under 21 CFR section 100.100, empty space can serve a legitimate purpose when it protects the food, accommodates packaging machinery, or results from unavoidable settling during shipping. The rule also recognizes certain package functions, genuinely reusable containers, and practical limits on filling or making a container smaller. The mere presence of air in a package does not establish a violation.

A slack-fill class action may allege that an opaque package looked fuller than it was and led shoppers to expect more product. The dispute often turns on the package design, the actual fill level, any functional reason for the space, and what a reasonable shopper would understand. A complaint is an allegation, not a court finding. A settlement can resolve the dispute without the manufacturer admitting that its package broke the law.

The federal food rule does not automatically govern every product sold in a box or bottle. Nonfood items can be covered by different federal or state consumer protection standards. Even for food, state law claims may raise questions beyond the federal rule. The applicable product, jurisdiction, and facts determine the legal test.

For Claim readers, slack fill describes the packaging issue, not who qualifies for a payment. If a related settlement appears on Claim, the covered products, purchase dates, proof rules, and payment terms come from that case’s approved documents. A package with noticeable empty space alone does not establish eligibility. Readers can compare the product and purchase details with the case information shown in Claim’s settlement directory.