Can I patent a song, poem, slogan, idea, etc.?
No. A copyright is the appropriate form of protection for works of authorship. You need not register your work of authorship until you need to enforce your copyright, which is created automatically. You can register your work at the web site of the U.S. Copyright Office. A copyright cannot be used to protect titles, names, short phrases, slogans, ideas, procedures, methods, systems, processes, concepts, principles, discoveries, devices, standard calendars, height and weight charts, tape measures and rulers, or lists or tables taken from public documents or other common sources. Learn more about which form of intellectual property protection is best for your creation by reading my Inventor's Guide.http://www.webpatent.com/content/answers.htm#auth
Q: How can I protect a slogan?
A: Let me repeat a well known quotation (or slogan?) and say "It ain't easy."
First, slogans, no matter how clever or how original, are not considered to embody sufficient original authorship for copyright protection. The U.S. Copyright Office will bounce your application.
Note that the U.S. Copyright Office does not judge the merit of someone's work. It can be a mediocre painting or a tedious article, or even a lousy poem, and it will be registered (provided of course that the required information is provided, on the correct lines).
In refusing to register slogans, the Copyright Office is not passing judgment on the merit of the slogan, but on the nature of the work as a mere slogan. The sufficient authorship requirement goes at least in part to policy as to what, and what not, can be held away from the public domain.
Second, a number of years ago it became trendy to place a trademark right up on the front of the product. My best guess is that the trend started with the little alligators. The little alligators were shown on the pockets of the shirts. Since the little alligators told everyone that you were wearing an upscale (expensive) brand, the alligators drove sales. The other manufacturers began adding their brand names to the front, and that drove sales too. Then even the off-brand brands came to the front, but that gets to a different story.
Well since putting the brand name on the front was now conventional, some folks successfully protected their slogans under trademark law, by selling t-shirts etc. with the slogan on the front and a prominent "TM" symbol.
This practice went on for quite a long time before the USPTO started clamping down on it. It still can be done, but not as easy as just slapping it on the front of a t-shirt or whatever. In fact, if a t-shirt front is your use specimen, registration will be undoubtedly be refused as merely ornamental use.
In addition, although trademark law does not require original authorship, common slogans and common symbols are excluded from trademark protection even if you establish appropriate trademark use.http://www.noreklaw.com/slogans.htm