Tellabs drops on AT&T concerns

Tellabs Inc., the Naperville-based maker of telecommunications equipment, dropped as much as 8.1 percent in Nasdaq Stock Market trading on concern it will lose some business at customer AT&T Inc.

Tellabs Chief Executive Officer Rob Pullen said on a conference call today AT&T is testing another equipment supplier for its high-speed network.

That's weighing on the stock, said Lawrence Harris, an analyst at CL King & Associates in New York. Tellabs fell as much as 63 cents to $7.16 and traded at $7.37 at 1:20 p.m. New York time.