We urge caution in that regard - using stock art in your logo is probably a violation of the terms of your agreement with the site where you bought the image.
Stock Art / Clip Art
If stock art or clipart is used, you must identify it as 'not yours' by indicating you do not own copyrights.
You may have this question: 'But I bought the rights on a stock image website! Therefore, I can use them, right?'
Answer: No, the probability is, you can't. The reason being that purchasing rights to use an image most often excludes the right to use it in making a logo or brand identity that will be permanent. Doing so would violate the limited rights the designer of that image gives you. Please carefully read the specific and general terms of the site you use to get the image(s).
If you have taken a picture with your camera or have some other kind of drawing or artwork that is yours or has been given to you with no legal strings attached, you may identify it as 'yours' and Designer may use it in their designs.
Copyrighted logos are often provided as part of the contest process. For example, a client may want to make a special logo as part of a sponsored event by a well-known local or international company.
Using such logos along with the contest submissions cannot be used on LogoTournament.com to create a new design, however the logo can be provided as a reference to make a placeholder.
Why? Established brands want to keep brand recognition and purity, therefore they almost always have a strict usage guideline in the manner of a PDF or other documentation. Such a document will outline to designers and event coordinators acceptable and unacceptable uses for the branded logo. Such uses might include where the logo can and cannot be placed when used with a secondary event logo, and color palette considerations.
Therefore, we recommend designers only use a stripped version of the logo (perhaps the outline only) for placement purposes only or simply put in another shape to identify where the company logo will be relative to the sponsor(s') logo(s). This is because they are selling their design, not their design and the branded company logo.
The copyrighted logo could be inserted after the contest is complete.
Any designs that are found to include (or suspected to include) limited-rights images or copyrighted logos will be flagged and removed by Admin staff.
Copyrighted, Original Artworks (Paintings, Drawings and Sculptures)
Copyrighted artworks are often provided for reference only as part of the contest process. For example, a client may see a painting, drawing or picture of a sculpture by some artist and want to use that as inspiration for a logo. This in itself is not usually a problem if the derivative work is obviously different.
Problems arise when a client may think: "I've paid for this art, or I own the photo of this art, therefore it's mine." This is possibly true. However, some artists may retain certain rights when they sell you art, or when it is sold to others. For example, a painting artist who produces prints of an original likely retains all printing rights to the art. Or a commissioned artist may retain certain visual media rights to a sculpture. You may not be able to use it for the purpose of making a logo or other derivative artwork without the copyright holder's permission. Generally, sculptures on display in very public places are copyright free, but it's important to do your research.