What is a trademark or service mark?
Important Databases - United States Patent and Trademark Office
USPTO Design Search Code Manual - if your mark includes a design element (i.e. logo), you will need to search it by using a design code
Trademark Electronic Search System (TESS) - This search engine allows you to search the USPTO's database of registered trademarks and prior pending applications to find marks that may prevent registration due to a likelihood of confusion refusal. Includes records back to 1984.
TEAS - the Trademark Electronic Application System - for online filing.
TSDR - Trademark Status & Document Retrieval - allows you to see the filings of others.
Conducting a Trademark Search - advice from staff at the USPTO
Including the important consideration of Likelihood of Confusion
Also, see the section on business name searching, below
State Trademark Information
State Trademark Information Links - find information on trademarks specific to all 50 states and D.C.
More Information, including World-Wide Searching
For Historical Investigation
The name of a business may also be used as a trademark but the two aren't exactly the same.
The Small Business Administration has detailed business name advice, also including domain name (website address) as a business name.
Trying to Avoid Business Name Conflict:
Business directories are a good place to check for organization names that are already in use. Here are two with broad coverage:
Claiming a name and for possible searching:
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