Read the contest rules!
For example, here's an excerpt from the rules for the "Live The Cover!" contest by Condé Nast Traveler in 2007.
All Submissions become the exclusive property of Sponsor, and none will be acknowledged or returned. Sponsor shall have the right to edit, adapt, and publish any or all of the Submissions, and may authorize others (including advertisers) to do so, and may use them in any media for any purpose, including but not limited to editorial, promotional, and advertising purposes, without attribution or compensation to the contestant, his or her successors or assigns, or any other entity. ENTERING A SUBMISSION IN THIS CONTEST CONSTITUTES PARTICIPANT'S IRREVOCABLE PERMISSION AND LICENSE TO THE FOREGOING USAGE, THROUGHOUT THE WORLD.
Condé Nast Traveler
Read the fine print on contest entry forms to:
• Avoid relinquishing your copyright or your granting of unlimited-usage rights.
You may be flattered to see your photograph used as part of an advertisement until you realize that the corporation is using for free.
You may agree to allow the organization or company to use your photographs for limited usage, such as the promotion of the contest, for a limited period of time.
• Avoid indemnifying the organization or company from lawsuits from their usage of your photographs.
For example, let's say XYZ Company uses your photograph of Jane Doe for advertising.
You didn't get a release from Jane Doe.
Jane Doe will sue you, not the company, because you indemnified the company.
Apogee Photography Internet Magazine Bimonthly Contest
Art of Photography Show February
Atlanta Photojournalism Seminar Contest
BBC Photographer of the Year Contest
Bethesda International Photo Competition Fraser Gallery, Washington, DC
Camera Club of New York National Juried Photography Competition
Everyman Photo Contest October deadline
Hey, Hot Shot! jen bekman gallery
Nikon:
Small World Contest April
Pictures of the Year International
Popular Photography International Picture Contest July
Soho Photo:
International Photography Contest Annual, April
Krappy Camera Contest Annual, December
SFCP Project Competition Annual, December
Semaine Photo de Riedisheim International Contest
Smithsonian Magazine Annual, December
virtual * visual : people - places - things By Women In Photography International
UNEP International Photographic Competition on the Environment United Nations
Visions of Science Annual, May deadline