Ecosse Hospital Products has filed a complaint with the Illinois Court of Claims asking the state to pay nearly $2.6 million.
The dispute arose because Blagojevich hired the company but never got federal approval to bring the flu vaccine into the United States.
Illinois Comptroller Daniel Hynes then refused to release money to pay for the vaccine. He argues the contract says Illinois does not have to pay if regulatory problems interfere.
But Ecosse disagrees. The company says it kept its part of the bargain and provided the vaccine. Now, it accuses Illinois of breach of contract for not paying.