A former General Casualty Insurance manager pleaded guilty Friday to embezzling about $560,000 from the company from 2003 to 2008.

Douglas A. Nickerson, 45, of Janesville, faces a maximum sentence of 10 years in federal prison when he is sentenced on Feb. 16. Nickerson admitted to U.S. District Judge Barbara Crabb that he issued General Casualty checks to other people who cashed the checks and then returned most of the money to him.

Nickerson, who was a property program manager with General Casualty in Sun Prairie, pleaded guilty to misappropriation.

He was indicted in June, along with David A. Janssen, 47, of Oregon, owner of Heartland Associates general contractor, who was charged with aiding and abetting misappropriation.

According to the indictment, Nickerson had checks written to Janssen and two other people, concealing the money in large, otherwise legitimate insurance claim files. Janssen and the others deposited the checks, kept a portion of them and gave the majority of the money back to Nickerson.

In all, more than $800,000 in General Casualty checks were issued, of which Nickerson retained about $560,000.

Nickerson said Friday that Janssen believed that the checks he received were for legitimate projects.

"He was under the assumption we were working on true projects and we would be splitting the general contractor fee," Nickerson told Crabb.

The aiding and abetting charge against Janssen was dismissed last week by federal prosecutors, who wrote in a court document that Janssen will instead plead guilty to a violation of federal tax laws for failing to report the money he received from Nickerson to the Internal Revenue Service.