A large scale manufacturing process to produce a recombinant antibody fragment utilizing a high cell density (HCD) E. coli fermentation was developed.  The process proved to be reproducible at both the small and large scale. Early process development work was performed with small scale bioreactors and included varying peptones, feeds, pH, temperatures and hosts.  The small scale soluble product yield was 6.0 g/L ± 1.5 g/L; this process was scaled up to develop a large scale fermentation process.