This file depicts the coat of arms, banner, or emblem of Mexico, one of its states, municipalities, or any other political subdivision, or a similar distinctive symbol belonging to an international or "recognized" organization, or NGO, operating in or outside of Mexico. According to Mexican federal copyright law, article 14 subparagraph VII, these coats of arms/banners/emblems are not eligible for protection under the federal copyright law.
According to the Mexican copyright law (23-07-2003), Article 14, case 7 & 8: "Copyright shall not apply to shields, flags or emblems of any country, state, municipality or political division; names, acronyms, symbols or emblems of international governmental organisations, or any other organization officially recognized; or legislative, regulatory, administrative or judicial texts, as well as their official translations."
Hence it is assumed that this image has been released into the public domain.