The Trump Organization may have run afoul of the law in ordering tee markers for golf courses featuring the Seal of the President of the United States, ProPublica has reported. Federal law limits the seal’s use to official government business and misusing it can be a crime.

According to the ProPublica article, it is unclear how many Trump International golf courses could feature the markers. The Trump Organization owns four golf courses with the “International” name in Florida, Scotland, Ireland and Dubai.

The situation illustrates the importance of brand protection. Presidential administrations have kept tight control in the past over the likeness of the seal that was first introduced in 1850 and redesigned in 1945. Presidents George W. Bush and Barack Obama used the seal on sets of golf balls, and the Reagans had a set of presidential china bearing the seal. The concern with the latest use is that it’s by a private company.

In 2005, when lawyers for the Bush White House contacted the satirical website The Onion over its use of the presidential seal on its website, Associate Counsel Grant Dixton wrote that the seal “is not to be used in connection with commercial ventures or products in any way that suggests presidential support or endorsement.”

The U.S. code states that anyone who displays the seal in “a manner reasonably calculated to convey a false impression of sponsorship or approval by the Government of the United States or by any department, agency, or instrumentality thereof, shall be fined under this title or imprisoned not more than six months, or both.”