UPDATE: In an email to partners Sept. 23, Travel Ad Network (TAN) president Brian Silver, referring to Travel Spike, says "a company has filed suit against Travel Ad Network to coerce TAN into paying excessive fees to resolve claims of alleged trademark infringement based on TAN's use of the brand "Travel Ad Network."
"TAN has used the brand Travel Ad Network continuously since early 2003," Silver says, adding:

TAN has tried unsuccessfully to resolve this matter in an amicable way, but has been frustrated at every turn. Know that we will not only defend ourselves, we will also pursue our own actions as necessary to bring this matter to a close. Meanwhile, we will continue to deliver you, our partners, the highest level of advertisers, products, and services now and for many years to come.
Interestingly, regarding the trademark dispute, Silver's email contains the logo and company, TAN media group, with the tagline "100% Travel Qualified."
The original post follows:
Travel Spike took its trademark infringement dispute with Travel Ad Network to court and is seeking damages and all profits TAN derived while allegedly illegally using the Travel Ad Network trademark and domain.
Atlanta-based Travel Spike operates an ad network considerably smaller than TAN's, but Travel Spike alleges that it used the name before TAN and secured trademark registration for Travel Ad Network from the US Patent and Trademark Office on Feb. 1, 2011.
Travel Ad Network brought in a new CEO with a WebMD pedigree earlier this month, is strongly hinting about changing its name, and is refining its mission into becoming a leading "travel news and information brand."
Travel Spike and TAN had been in discussions about the dispute earlier this summer, but the litigation obviously signals that no settlement has been reached.
Travel Ad Network has raised $31 million in funding to date, including a $15 million Series C round led by Starvest Partners and announced in October 2010.
The suit was filed in US District Court for the Northern District of Georgia.