In a letter sent to Wikipedia's San Francisco office, the FBI said that "unauthorised reproduction of the FBI Seal was prohibited by US law". "Whoever possesses any insignia...or any colourable imitation thereof..shall be fined...or imprisoned... or both," the FBI wrote. However, Wikipedia denied that it had done anything wrong and said that FBI lawyers had "misquoted the law".
The issue centred on FBI's Wikipedia entry which, in addition to information on the US bureau, also features an image of the "Seal of the Federal Bureau of Investigation". The image can be viewed in four different resolutions, including a high-resolution 2000px version.
The FBI said that this was "particularly problematic, because it facilitates both deliberate and unwitting violations of restrictions by Wikipedia users". It's not yet known why FBI has singled out Wikipedia, when the FBI seal is published on numerous other websites.