In late 2006, Pfizer agreed to pay $155 million for a tiny company called Embrex, which marketed a unique technology for innoculating poultry against various diseases. The deal was seen as a way for the drugmaker to bolster its animal health business. Now, though, three former Embrex execs, including former ceo Randall Marcuson, who led the company for 16 years before it was sold, claim in a lawsuit that Pfizer reneged on compensation and benefits they were promised, The News & Observer reports.

After the deal closed, Marcuson; Joseph O’Dowd, who oversaw product development and supply, and Don Seaquist, who was in charge of finances and administration, were all fired last year, the paper adds. Although the deal made Marcuson and Seaquist into millionaires, their dispute with Pfizer is about disability insurance and tax reimbursements they say they are entitled to receive. A spokesman for Pfizer, Rick Goulart, tells the paper that the drugmaker is in compliance with the contracts.

But the execs claim in their lawsuit that they are entitled to reimbursement for state and federal income taxes they will incur on lump-sum payouts from Embrex’s retirement plan. They say Pfizer has indicated it will not honor the agreements. In the lawsuit, filed last month in a state court, they ask for unpaid wages, damages and attorney’s fees, according to the News & Observer.