A federal appeals court has affirmed a judge's decision to let stand Minnesota's law requiring the disclosure of corporate political donations, saying the state's rules are similar to laws upheld by the Supreme Court and the groups who want them blocked are unlikely to prevail.

In an opinion filed Monday, the 8th Circuit Court of Appeals disagreed with claims that Minnesota's disclosure requirements effectively prohibit corporate independent expenditures and impose burdensome regulations that ban free speech.

"The burden on corporations appears light, and the reporting requirement greatly facilitates the government's informational interest in monitoring corporate independent expenditures," the appeals court found. The judges wrote that rather than banning contributions, the law provides a way to disclose certain information.

Minnesota law requires that in election years, businesses and independent groups must submit five reports and disclose large donations within 24 hours for the three weeks leading up to the primary and the last two weeks before the general election. In off years, one report is required. The registration requirement is triggered when businesses or independent funds spend more than $100. Penalties for violations can be up to $25,000.

One member of the three-judge panel disagreed with the majority in part, saying the state's reporting requirements chill political speech.