On Aug. 26, 1991, Cellpro announced its initial public offering. CellPro, founded in Bothell, developed the CEPRATE SC stem-cell concentration system for use in bone-marrow transplantation. In 1996, the FDA gave marketing approval to the company’s CEPRATE SC stem-cell system for use in bone-marrow transplantation.

In 1997 CellPro was involved in a patent-infringement lawsuit brought by Johns Hopkins University, Baxter International, and Becton Dickinson & Co. concerning an antibody used in the CEPRATE SC stem-cell system treatment. In March, 1997 a federal district court jury ruled in favor of the plaintiffs, and in the end, CellPro paid more than $15 million to settle the lawsuit and declared bankruptcy in 1998.