Once you've designed a new logo, how does one go about registering or trademarking the logo?

How do you register or trademark a slogan?

How can you be sure that your logo and slogan don't infringe on those held by another company?

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What country are you deploying the logo in?

As far as copyright is concerned, in the UK at least, copyright is automatically assigned to the creator of the work be it graphic, literary, music etc, etc...

1/2. Registering and trademarking is usually handled by government departments. In the UK, it's http://www.patent.gov.uk/

3. You can't. Well, you can't be absolutely sure. No one can. Even if two companies get involved in a dispute over logos, the courts will probably decide the outcome. In my experience, two companies who have roughly similar logos can co-exist providing they are in different spheres of operation e.g. Toiletries and DVD Sales outlet. The courts would decide whether the public could be confused by the mark. In most cases, it's quite unlikely.

Finally, I'd say that if you've got any niggling doubts about a logo infringing another mark, it probably does!!! :)

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Logo Design • Vector Conversion • Print
www.eagleimagery.co.uk

If in US, try these links:
http://www.uspto.gov/teas/
http://www.uspto.gov/main/trademarks.htm

Like the UK, the US uses different "classes" for each logo, like Education, Internet, Merchandise, etc.

So, I believe in the US if you have the same or a really similar logo to another company that is in a different class then you can co-exist with no problems.

But, you should probably check with an attorney.

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