Google has rolled out a limited test of a new banner ad for Southwest Airlines that will display atop the results page for queries about that company, contradicting a long-standing pledge to never run such advertising.

The banner appears front-and-center on the result page for "southwest," just above a set of links to different parts of the airline's website. A small "sponsored" notation is visible at the upper-right of the ad, with a pop-up explanation that "based on your search query, we think you are trying to find a specific brand," and confirms that the brand is paying for this placement.

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Marissa Mayer who was then Google's vice president of search products wrote in an official blog post in 2005 that "there will be no banner ads on the Google homepage or web search results pages. There will not be crazy, flashy, graphical doodads flying and popping up all over the Google site. Ever."

That appears to no longer be the case, however a Google representative confirmed that the company is testing new banner ads "that show in response to certain branded queries," noting that the rollout is a limited trial that will appear to U.S. users only.

Since 2005, the trend has been away from the plain blue-on-white list of links and towards the integration of more image-heavy advertising on the company's search result pages. The Google rep cited image extensions, product listing ads, and media ads as examples.

The company's advertising business has continued to grow over the past year, booking multi-billion-dollar increases in each of the last four quarters. Google's latest quarterly report says that advertising accounted for $13 billion in revenues over just three months.

Email Jon Gold at [email protected] and follow him on Twitter at @NWWJonGold.

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