Restoring the 10th Amendment Act - Authorizes a designated state official to submit to the head of a federal agency proposing a rule, during the period when the proposed rule is open for public comment, a legal brief challenging the constitutionality of the rule under the Tenth Amendment to the Constitution.

Directs the agency head: (1) to notify the designated official of each state within 15 days after such a brief was submitted; (2) to post prominently on the front page of the agency's website a link to the brief; and (3) within 15 days after posting such link, to certify in writing that such rulemaking does not violate the Tenth Amendment and post the certification prominently on the agency's website next to the briefs pertaining to the rule, unless the agency determines not to finalize such proposed rule.

Authorizes a designated state official, at any time after an agency head posts such a certification, to commence a civil action against the agency on the grounds that the rule violates the Tenth Amendment. Permits such state official, in addition to any other venue or jurisdiction provided by law, to bring such action in the U.S. district court for the district in which the official's place of business is located.

Directs the appropriate U.S. court of appeals, upon the filing of a notice by a designated state official, to grant expedited review of a decision by the district court in such an action.