- ”mouse print” is the fine print in advertising, in a contract, or on a product label, often buried out of easy sight. In the worst cases, the mouse print changes the meaning of, or contradicts the primary claims or promises being made. Sometimes, the catch is not even disclosed. In other cases, the fine print is merely an unexpected surprise for the reader. Fine print is not inherently illegal. But, advertisers are not safe from false advertising claims merely because an ad discloses the truth in some minimal manner.