Illegal stamps

Illegal stamps have been defined by the General Meeting of the AMDP (Worldwide Association for Philately Expansion), during its second meeting (October 6, 2000) as illegal issues by territories having no right in issuing stamps, or forged issues produced by defrauders in the name of an authority having the right to issue stamps, with the intention of cheating collectors.  Examples - a typicel example is the "omnibus" set Bénin/Congo/Timor.
The U.P.U. (Universal Postal Union) fights these pirate issues and regularly publishes related circulars. That is also the reason for the creation of the WNS, the authentic postal stamps numbering system of the U.P.U. members.

How to recognize forged stamps?

The most difficult when a stamp is produced is to make a regular perforation, mainly in the stamps corners. Harrow perforations or comb ones need expensive hardware and are not profitable for the forgers. They prefer use perforation in line, from which result these shifts in the corners:

You can see very well on the above sheet the shift of the perforations in the corners of the stamp. Assuming that the Tanzania official stamps do not have this problem, it can be concluded that this shhet is false.

When the postal administration has on another hand an official philatelic web site, you can go to this site to check the legal issues (for exampe, Tanzania web site is: If the country has a philatelic website, a link is put on its postal administration logo at the top of the page dedicated to this country, as for example:

    Tanzanie / Tanzania 

And finally, auction sites like for example Delcampe try to survey this kind of stamps, so that they are clearly identified as cinderellas during the sales process.