Pipe makers have been marking their pipes for as long as pipes have been around. In fact, experts have used pipe marks to date pipes that have been passed down to the future from their 15th, 16th, and 17th century owners. The marks and logos are typically directly imprinted on the stem or bowl of the pipe and are either raised or recessed. The great thing about pipe marks is that they can help both new and experienced collectors identify the manufacturer of a particular pipe. This can be extremely helpful when purchasing pipes from people or estates.
There are several resources available that list the numerous pipe marks and logos and the associated manufacturers. The most comprehensive resource, however, can be found online at the PipesPhil.eu website. This non-commercial site contains pictures of each logo and people can search for manufacturers by brand name, country of origin, or style of logo. For example, there is a section for logos with dots and/or spots and one for logos with geometrical patterns.
Another good resource is the World Hallmark website. This site contains an extensive listing of silver marks, hallmarks, trademarks and maker's marks that have been imprinted on antique and vintage silver. Though it is not exclusive for identifying pipe marks and logos, it is an especially good place to go for figuring out the makers of antique pipes.
Here is a brief listing of some of the popular pipe manufacturers and their associated marks and logos: