John Richards has updated his on-line article on utility model protection. It is well worth reading. Utility Models, which are also known as Petty Patents, are a type of intellectual property protection not available in the United States, but which is available in a significant number of countries outside the US.
More significantly, for some types of invention, use of a petty patent or utility model as a means of protection may be a useful alternative to traditional patent protection in many countries. Obtaining protection this way is often much less expensive than proceeding through the traditional patent route and, as noted in the article, in several countries has an advantage in its own right. Such protection can be obtained either by direct filing or by use of the Patent Cooperation Treaty. Read on.