Products that are considered a 'Health' Food must be registered with Health Canada to be legally sold to the Canadian public. Products like Chaga Mushroom must be licensed with the Natural and Non-prescription Health Products Directorate (NNHPD) and issued a valid NPN number. This is your assurance that the Chaga you are taking has been found to be safe, effective and of high quality under their recommended conditions of use.
More information is available at the Health Canada website. You can also access the Health Canada Licensed product database to lookup currently active NPN product numbers.