The accident occurred on Interstate-84 near Pendleton, Ore., on Dec. 30 after the bus operated by Mi Joo Tour & Travel crashed through a guardrail and tumbled down a snowy embankment.
The Oregonian newspaper reports that 74-year-old Eun Sook Uhm of Lynnwood, Wash., is suing the company and seeking unspecified damages for herself and her husband, who was not on the bus.
She remains hospitalized at Harborview Medical Center in Seattle, Wash., with injuries described in the lawsuit as "severe and permanent."
The suit, one of several filed against the Coquitlam, B.C.-based tour bus company, alleges it allowed the bus driver to work without proper rest.
Tour company lawyer Mark Sheer has said the driver had plenty of sleep before the crash and that black ice was a major factor.
Oregon State Police continue their investigation. The tour company has been barred from operating in the United States and Canada.
None of the allegations contained in the lawsuits have been proven in court.
Also on HuffPost