Besides the trademarks used to represent the commercial origin of a product or service, there are some special kinds of trademarks: collective marks and certification marks.
A collective mark is registered in the name of industrial and commercial groups, associations or other organizations and used to demonstrate the user's membership in the organization. Through the use of the collective marks, the members can demonstrate that they are in conformity with the quality requirements and standard set up by the organization (such as the accountant association or the engineer association).
A certification trademark is used to certify the origin, raw material, producing technique, quality or other specific quality requirements. Any one can apply for the use of certification trademark as long as his product or service's quality matches the specified standard. For example, the "ISO9000" is one kind of universally acknowledged certification trademark.