A Rohnert Park man entered a plea Wednesday sending him to prison for embezzling more than $1 million from his Petaluma employer, who said the company will be affected for years to come.

The stolen funds drove Bibbero Systems further into financial stress during a time when the company was forced to downsize, according to owner Mike Buckley. Bibbero lost half of its employees through layoffs and attrition during the past six years, he said.

Under the plea bargain deal, John C. Sheehan, 43, pleaded no contest to grand theft, receiving stolen property and tax evasion and agreeing to serve nine years and four months in prison.

Sheehan will turn over two cars, an array of electronics and at least $50,000 to his former employer, Bibbero Systems, prosecutor Amy Ariyoshi said.

Bibbero owner Buckley said the forfeited assets, which include two Mercedes-Benz cars, will bring little financial relief to the company and cannot restore the trust lost among employees.

"It is going to effect everyone in the company for quite some time to come," Buckley said. "Everyone is so paranoid. They're checking every bill. They're bringing every question my way."

Sheehan also accepted several white-collar crime enhancements that ensure he will serve his time in state prison and not jail.

Sheehan, whose original name was John Christopher Schoenthal, spent 15 years working for Bibbero, a medical and business filing products maker. He was the head of management information systems.

Sheehan began a scheme in 2006 in which he created a fictitious company to bill for office supplies never received, investigators said.

He wrote checks several times a month ranging from several hundred dollars to $1,000, Ariyoshi said. He cashed checks in his name and spent some of the money on a major home remodeling project that included 14 flat-screen TVs and an expensive security system.

Meanwhile, Bibbero, already struggling to navigate the shift in medical documents from paper to electronic, was forced to down-size, Buckley said.

Bibbero Systems had four employees when Buckley and his wife acquired it from his father-in-law in 1978, he said. The company grew to about 150 at its height in 2006.

They have since downsized to about 75 employees, at least in part due to money lost to Sheehan, Buckley said.

Sheehan only came under suspicion after a manager, curious about an invoice, did an Internet search for the fake company. The manager called police in July after discovering the phone number was disconnected. Petaluma police arrested Sheehan Aug. 2.

Sheehan attorney Walter Rubenstein said his client was eager to bring a swift end to the case.

"He took responsibility and he felt bad in regard to the impact of other people," Rubenstein said.

Buckley and several employees were planning to read statements at Sheehan's Nov. 20 sentencing hearing.

"It's moving-on time for all of us," Buckley said.

You can reach Staff Writer Julie Johnson at 521-5220, julie.johnson@pressdemocrat.com or on Twitter @jjpressdem.