It looks like this forum needs some new additions. As noted, one of my philatelic endeavors is forgeries. I will post links to some of my files that have been updated for eventual publication. First some definitions might be in order... Forgery: an unlawful reproduction of a stamp to either defraud collectors or the Postal Agency (government) - defrauding the government is technically called a counterfeit. Fake: a genuine stamp that has been altered generally to increase its value. Examples include trimming perfs to create an imperforate or adding perforations or altering them. Fake overprints or cancellations are a common problem. Exhibition or souvenir sheets with the stamps trimmed are also in this category. A fake can also be a "full forgery" in the case where a forgery/counterfeit has a fake cancel/overprint. Bogus: These are stamps that do not exist as opposed to those essayed or trials that were never issued. A bogus might include a non-existent design, value, color or country. "Phantom" stamps is another description. Reprints: these fall into 2 categories. Official reprints that were authorized by the government. Unofficial or private reprints that are not authorized. Sometimes one will read that a forger/dealer produced "reprints" with an original die. My thought (and others) is that if they are not authorized then they are forgeries. Facsimiles: These are reproductions of originals not intended to defraud collectors or the government. Often there is indication on the stamp face or reverse of the intention. They may have been produced for special events/exhibitions/commemorations/advertising. The facsimile might be altered to produce a fake.