Robert Nipar, 44, of Simi Valley, was sentenced to two years in state prison for embezzling more than $300,000 from Amgen Inc. of Thousand Oaks.

Nipar's co-defendant, Jason Rimmer, 37, of San Mateo, was an event planner who worked for Amgen. Rimmer provided Nipar with information to set up merchant accounts for fictitious businesses whose names were similar to Amgen's legitimate vendors.

Nipar then charge Amgen's American Express account for nonexistent services and forwarded the false invoices to Rimmer, who approved them for payment. Funds paid to the bogus invoiced were deposited directly into Nipar's bank account. The scheme lasted for about one year.

Nipar and Rimmer both pleaded guilty to felony grand theft in September 2007. The defendants repaid Amgen for all but $3,572 of the loss. Rimmer received a sentence of two years in state prison in April.