Over the past three years Motorola has fired off multiple rounds of dramatic corporate espionage claims against a small wireless network rival called Lemko Corporation. On Monday, Lemko and its lawyers at Niro, Haller & Niro went on the offensive, with a Chicago state court complaint accusing Motorola and two of its lawyers at Nixon Peabody of abuse of process and unfair competition.

The allegations relate to Motorola’s ongoing theft of trade secrets case against Lemko in Chicago federal district court, which Lemko claims was brought solely in order to ruin its business and reputation. In 2008, Motorola accused Lemko of conspiring with alleged spy Hanjuan Jin to smuggle confidential Motorola documents into China. Jin, an ex-Motorola software engineer and a naturalized U.S. citizen, was stopped by U.S. customs agents at Chicago’s O’Hare airport in 2007 carrying 1,000 company documents, $30,000, and a one-way ticket to China, according to the Department of Justice. (On Monday the DOJ delivered opening arguments in a bench trial on its criminal theft of trade secrets case against Jin in Chicago federal district court.)

Motorola amended its original complaint against Lemko in 2009, adding new allegations that inventor Pan Shaowei and businessman Nicholas Labun, two former Motorola employees that quit to form Lemko in 2004, took confidential information with them on their way out the door. Then, in July 2010, Motorola broadened its claims once again, accusing Lemko of reselling Motorola’s trade secrets to the Chinese telecom giant Huawei Technologies. Motorola dropped Huawei from the case in April, as we previously reported.

“We think that Motorola’s lawsuit was entirely motivated by an effort to destroy these guys,” Lemko counsel Raymond Niro Sr. of Niro, Haller & Niro told the Litigation Daily. Niro faulted Motorola for amending its complaint three different times with what he said were entirely different theories of the case. “What that says in a nutshell is that Motorola is searching desperately for a home for a legal theory that doesn’t exist,” he said.

Niro also said Motorola had pitched journalists a “blatantly false” story of the company being the target of a Chinese spy ring. And he lambasted Motorola for including Pan’s home address in their original complaint–a decision he said “was calculated to cause maximum harm.”

Chicago-based Nixon Peabody partner R. Mark Halligan, who is a named defendant in the case, declined to comment. Associate Deanna Swits is also named as a defendant.

Motorola called Lemko’s suit “frivolous” in an e-mailed statement. “Motorola Solutions is pursuing its rights vigorously in the pending federal action, and will defend against Lemko’s meritless lawsuit,” the company said.

In August, Niro moved for partial summary judgment on some of Motorola’s theft of trade secrets claims in the federal district court suit before judge Matthew Kennelly, arguing that Motorola has not narrowly identified the information Lemko allegedly stole. Motorola and Lemko, meanwhile, have both filed motions claiming they rightfully own Pan’s patent portfolio. Judge Kennelly could rule on those motions before the end of the year, Niro said.