AT&T Inc. (NYSE: T)'s decision to limit FaceTime on the cellular network to those subscribers with Mobile Share data plans is not a net neutrality violation, the carrier argued Wednesday morning in a blog post shooting down "knee jerk reactions" to its plan. (See AT&T Reserves 4G FaceTime for Data Sharers.)

Bob Quinn, head of AT&T's federal regulatory group, wrote that the carrier doesn't offer any competitive service to Apple Inc. (Nasdaq: AAPL)'s video chat app, so it's not in violation of net neutrality rules by limiting it to certain subscriber groups. (See AT&T Joins Verizon in the Shared Data Pool.)

"Nonetheless, in another knee jerk reaction, some groups have rushed to judgment and claimed that AT&T's plans will violate the FCC's net neutrality rules," he said. "Those arguments are wrong."

Net neutrality or Open Internet rules state that mobile broadband service providers cannot block apps that compete with their own voice or video telephony services. AT&T is basing its argument, first, on the fact that it doesn't have its own video chat service, and, second, on the notion that a preloaded app has different governing principles to a downloadable app. (See FCC Dings Verizon on 4G App Blocking.)

Quinn argues that FaceTime, as a preloaded app, is subject to reasonable restrictions, and limiting it to Wi-Fi on data plans where capacity might become an issue falls into that reasonable category. The carrier doesn't touch downloaded apps of the same nature, he notes, which could have implications for other video chat apps like Google Talk or Skype. (See Video Chat: Meet the New Data Hog.)

Within an hour of posting Quinn's blog, Free Press Research Director S. Derek Turner struck back that the rules make no such distinction between preloaded and downloaded apps and that AT&T's logic on the data usage makes little sense. He asks, if data traffic is an issue, why block FaceTime on a 3GB individual tier plan, but not on a 1GB shared data plan?

"FaceTime allows people to reduce their use of voice services, but AT&T is making you buy unlimited voice in order to use FaceTime over mobile," Turner said in a statement. "AT&T is trying to invent a loophole in the rules, but this kind of anti-consumer behavior is the exact thing the FCC's protections are designed to prohibit."

Sprint Corp. (NYSE: S) and Verizon Wireless have so far kept quiet on their plans for FaceTime. In AT&T's case, the Federal Communications Commission (FCC) may have the final say on the legality of its decision as the Free Press is trying to rally consumers to sign a petition urging the regulatory body to get involved.

— Sarah Reedy, Senior Reporter, Light Reading Mobile