Ricoh initially accused OKI of infringing five patents relating to printers and MFPs, dating back to a patent license agreement from 2001.
The agreement expired in 2006, but the two companies were unable to settle a new one, leading to Ricoh launching legal action in 2009.
The USITC then determined that only one patent had been infringed, but OKI said it was confident that there had been no violation, and appealed for a review.
In a statement, OKI Data said: “This determination is currently being reviewed by our attorneys and at this time the only information available is that both parties are requested to brief their positions on the issues under review with reference to the applicable law and the evidentiary record as well as their respective positions on the appropriate remedy should a violation be found.
“This notice is not the final decision; therefore, there is no impact on our products at this point. OKI Data Americas will provide further information when it is available.