(Updates with comments from Verizon Wireless and AT&T)

By Roger Cheng Of DOW JONES NEWSWIRES

NEW YORK -(Dow Jones)- AT&T Inc. (T) took offense to Verizon Wireless's recent "There's A Map For That" campaign, claiming in a lawsuit filed Tuesday that the commercials falsely suggest the wireless carrier has coverage gaps.

Verizon Wireless, which is jointly owned by Verizon Communications Inc. (VZ) and Vodafone Group Plc (VOD), has jumped on the mounting criticism of AT&T's coverage and its ability to handle the Apple Inc. (AAPL) iPhone with its recent commercials, which target AT&T's high-speed third-generation, or 3G, network. The commercials mock Apple's own "There's An App For That," television spots, which tout the thousands of programs found on its smartphone.

But in a filing, AT&T said the Verizon Wireless commercials mislead consumers about the scope of its coverage by using maps with large amounts of blank space. The white space indicates the lack of a 3G network, but AT&T contends that consumers see the blank spots as a complete lack of coverage. The company added that it had complained to Verizon Wireless, and minor changes had been made to the spots.

"By communicating that AT&T customers have no coverage in large parts of the country, Verizon is misleading the public about an essential component of the services AT&T offers," the lawsuit said.

Verizon Wireless dismissed the lawsuit.

"The suit doesn't have any merits," said spokesman Jim Gerace. "Our ads clearly explain that non-3G coverage is available elsewhere.

"I think it's interesting that AT&T's chose to focus on the white areas and not the blues area of their map. We think it calls into question their own fastest 3G claim as the map clearly shows where 3G doesn't exist."

AT&T has taken a large public hit on its spotty 3G coverage, which is crucial for smartphones capable of handling Internet browsing, videos and emails. Regardless, the carrier remains the leader in smartphones sold, driven primarily by the iPhone, but also as a result of high-profile devices by Research in Motion Ltd. (RIMM) and Nokia Corp. (NOK).

"Verizon knows we're the leader in smartphones," said AT&T spokesman Mark Siegel. "This whole campaign is a response to that."

Lawsuits over aggressive marketing campaigns aren't unusual. Last year, Verizon sued Time Warner Cable Inc. (TWC) over ads it felt misrepresented its FiOS fiber-optic television and Internet services.

AT&T fell 1% to $25.34 in recent trading, while Verizon fell 1.2% to $29.05.

-By Roger Cheng, Dow Jones Newswires; 212-416-2153; roger.cheng@dowjones.com

(END) Dow Jones Newswires

11-03-09 1532ET