Q What is the difference between a trademark, a copyright and a patent?

Amrit Chahal, San Jose

A A copyright protects work of authorship in any tangible medium, including books, plays, computer programs, movies, music, lyrics and choreography. Copyrighted material cannot be used by anyone else except under ``fair use'' laws, which allow, for example, book reviewers to quote parts of the books they review.

A patent protects inventions, including machines, methods, manufactured products, new uses of inventions, improvements on inventions and new designs for products. Genetically engineered life forms also can be patented. A patent prevents others from making or selling the invention in the country that granted it for a specified time. Patents used to last 17 years, but under the General Agreement on Tariffs and Trade they become valid for 20 years, effective June 8. Design patents, covering only a product's appearance, are valid for 14 years.

A trademark is a word or words, name, design, picture, sound or any other symbol that distinguishes the products of one company from those of another. A so-called strong trademark consists of a word with no other recognizable meaning, such as Kodak. These receive broader protection than weak trademarks, which consist of a common word such as Premier. A company with a trademark can prevent others in the same geographic area from using the same trademark or a similar one for the same kinds of products.

If you invented a book that turned its own pages, you could get a patent on the mechanism that makes it work. If you wrote a story to go in the book, you could get a copyright on the story. If you marketed a line of these books under a name like Autoturn (assuming that name isn't taken), you could get a trademark on the name.

Q&A on the News is written by Karl Kahler. If you have a question, call (408) 920-5003, fax (408) 288-8060 or write Q&A on the News, 750 Ridder Park Drive, San Jose, Calif. 95190.

Published 4/11/95 in the San Jose Mercury News.

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