Data throttling is a controversial topic between the carriers and regulatory groups. Data throttling is the intentional slowing of wireless service, and most recently AT&T was said to be throttling unlimited subscribers regardless of network conditions. Most carriers throttle data when the wireless network is congested, handing-off the connection from one cell tower to another until the network frees up. The Federal Trade Commission has sued AT&T for promising unlimited data to customers and then throttling their speeds by as much as 90%, the FTC announced in October. Now the FCC is stepping in. AT&T disclosed that the FCC is investigating the matter in a motion to dismiss the FTC’s lawsuit. “The FTC seeks to litigate the very same issues in an inappropriate parallel proceeding,” AT&T said in the motion to dismiss file this week. (GigaOm) AT&T believes that the company is out of the FTC’s jurisdiction because it’s a common carrier, and that jurisdiction lies with the FCC.