Frequently Asked Reference Questions

Patents, Trademarks, Copyright, Public Domain, and Fair Use

Example Questions That Can Be Answered Using This FAQ

  • What is a "patent"?
  • What is a "trademark"?
  • What is a "copyright"?
  • What does "public domain" mean?
  • What does "fair use" mean?
  • How do I patent my invention?
  • How do I trademark my business or product name?
  • How do I copyright the contents of my website?
  • How do I research whether a book is in the public domain?
  • How do I search through public domain books?
  • How do I search through patented inventions?
  • How do I search through trademarks?

Many IPL users want to know how to get patents, trademarks, and copyrights, or they want to know what kind of patent and trademark searching can be done on the Web. Here is a compilation of the best Web sites we have found.

What Are Patents, Trademarks, and Copyrights? What is fair use? What is the public domain?

According to Black's Law Dictionary (8th ed.),

  • A patent is "The right to exclude others from making, selling, offering for sale, or importing an invention for a specified period (20 years from the date of filing), granted by the federal government to the inventor if the device or process is novel, useful, and nonobvious."
  • A trademark is "A word, phrase, logo, or other graphic symbol used by a manufacturer or seller to distinguish its product or products from those of others. The main purpose of a trademark is to designate the source of goods or services. In effect, the trademark is the commercial substitute for one's signature. To receive federal protection, a trademark must be (1) distinctive rather than merely descriptive or generic; (2) affixed to a product that is actually sold in the marketplace; and (3)registered with the U.S. Patent and Trademark Office. In its broadest sense, the term trademark includes a servicemark. Unregistered trademarks are protected under common-law only, and distinguished with the mark 'TM.'"
  • A copyright is "The right to copy, specif[ically], a property right in an original work of authorship (including literary, musical, dramatic, choreographic, pictorial, graphic, sculptural, and architectular works; motion pictures and other audiovisual works; and sound recordings) fixed in any tangible medium of expression, giving the holder the exclusive right to reproduce, adapt, distribute, perform, and display the work."
  • Fair use (in copyright) is "A reasonable and limited use of a copyrighted work without the author's permission, such as quoting from a book in a book review or using parts of it in a parody. • Fair use is a defense to an [copyright] infringement claim, depending on the following statutory factors: (1) the purpose and character of the use, (2) the nature of the copyrighted work, (3) the amount of the work used, and (4) the economic impact of the use. 17 USCA � 107. [Note: the link is to the United States Code; the reference in the definition is to the United States Code Annotated, which is not available for free on the Web.] — Also termed private-use exception; (in Canadian law) fair dealing."
  • Public domain (in intellectual property law) is "The universe of inventions and creative works that are not protected by intellectual-property rights and are therefore available for anyone to use without charge. • When copyright, trademark, patent, or trade-secret rights are lost or expire, the intellectual property they had protected becomes part of the public domain and and can be appropriated by anyone without liability for infringement."

Patents, trademarks, copyrights, and issues regarding public domain and fair use are part of an area of law called intellectual property law.

Cornell Law School's Legal Information Institute (LII) has an overview of its intellectual property law articles, as part of its legal encyclopedia and dictionary WEX. (WEX is collaboratively written and edited, like Wikipedia. But it is much more authoritative than Wikipedia, because unlike Wikipedia, WEX contributors must be subject-area experts–usually holders of law degrees, and often law professors. See the WEX FAQ for more details.)


The U.S. Patent and Trademark Office (USPTO) homepage has news about patents and trademarks, conference announcements, and links to legal materials.

The USPTO has a "General Information Concerning Patents" Web page (which also has information about trademarks and copyrights).

The USPTO has a Web page devoted to patents.

The LII's WEX has an excellent overview of patent law.

The University of Michigan's Art, Architecture, and Engineering Library has a good guide to patents and trademarks, which includes patent search tips and a link to the Canadian patent database.

Nolo Press, the legal self-help publishing company, has a Web page on "Patents, Copyright, and Art."

The Patent Information Users Group, Inc., has a list of "Patent FAQ Sites"

Stanford University's Swain Chemistry and Chemical Engineering Library has a general patent information page. (There are more links to other patent-information Web pages towards the top of that page, under the name of the library and the word "Patents.")


The USPTO homepage has news about patents and trademarks, conference announcements, and links to legal materials.

The USPTO has a Web page devoted to trademarks.

The USPTO has a "Trademark FAQ".

The LII's WEX has an excellent overview of trademark law.

The University of Michigan's Art, Architecture, and Engineering Library has a good guide to patents and trademarks, which includes patent search tips and a link to the Canadian patent database.

Nolo Press has a trademark information page. Nolo's Web page on "Patents, Copyright, and Art" also has information about trademarks.

The LII's WEX also has a Web page on unfair competition law. Infringement (unlawful use) of trademarks is a type of unfair competition.


The U.S. Copyright Office main page has lots of information. It has a Copyright Basics page, and a presentation, "Taking the Mystery out of Copyright," for teachers and students.

The USPTO has a Web page devoted to copyright.

Brad Templeton has a Web page called "Ten Big Myths About Copyright Explained," which does what it says it does, and a companion Web page, "A Brief Intro to Copyright."

(Brad Templeton has excellent credentials as a lay copyright expert (that is, he's not a lawyer). He "was the founder and publisher of ClariNet Communications Corp., the world's first ever '.com' company…and which was also the net's first and for a long time largest electronic newspaper." He is also Chairman of the Board of the the Electronic Frontier Foundation, "the leading foundation protecting liberties and privacy in cyberspace.")

Nolo Press has a Web page on "Patents, Copyright, and Art."

The LII's WEX has an excellent overview of copyright law.

The American Library Association has a copyright issues Web page.

The Cornell Copyright Information Center has a Web page on "Copyright Term and the Public Domain in the United States."This highly useful table, created by Peter B. Hirtle, the Intellectual Property Officer for the Cornell University Library, shows how long copyrights last and when intellectual property falls into the public domain. The table is also available as a PDF file. A PDF reader will be needed to access the PDF file.
Free Adobe Acrobat Reader Download link

Indiana University-Purdue University-Indianapolis has a Copyright Center.

The University of Texas has a "Crash Course in Copyright."

Public Domain and Fair Use

"Public domain" is defined above, in the definitions section.

Stanford University Libraries has a Web page about fair use.

An FAQ on How do I find out whether a book is in the public domain? is part of The Online Books Page at the University of Pennsylvania's Libraries.

Researching Existing Patents, Trademarks, and Copyrights

Patents cannot be researched completely via the Web, as, according to USPTO, "Patents issued from 1790 through 1975 are searchable only by patent number, issue date, and current US classifications." (See "Important Notices concerning the Patent Full-Text and Full-Page Image Databases.") Nonetheless, users may find the following resources in this section useful in their search.

The USPTO database of patents available on the Web is available here.

USPTO has a Web page with a seven-step patent search strategy.

Google has a patent search engine, currently in beta (open to users, but still being tested). (For more details, see Google's patent search help.)

To search trademarks on the Web, use USPTO's Trademark Electronic Search System (TESS).

But all patent and trademark information may not be available on the Web. To conduct a more thorough search visit a Patent and Trademark Depository Library, which will have more comprehensive databases of patents and trademarks. USPTO's Web site has an overview of the Patent and Trademark Depository Library Program, which includes a listing of libraries, with phone numbers, by state.

Stanford University Libraries also has a "Copyright Renewal Database." As the database description says, "This database makes searchable the copyright renewal records received by the US Copyright Office between 1950 and 1992 for books published in the US between 1923 and 1963." If used carefully, the database may help determine if a book (the database only covers books) published and copyrighted in that time period is in the public domain.

The Patent Information Users Group, Inc. has a list of "Patent FAQ Sites."

Substantially revised and expanded by Mitchell L.