From The Truth About Guns:

At the time, Gov. Parson said the unique law “draws a line in the sand and demonstrates our commitment to reject any attempt by the federal government to circumvent the fundamental right Missourians have to keep and bear arms to protect themselves and their property.”

On Monday, however, a three-judge panel of the 8th Circuit Court of Appeals upheld last year’s district court ruling and found that the Missouri law violated the U.S. Constitution’s supremacy clause, which states that federal law takes precedence over state laws.