Protein refolding is a process of recovering protein aggregates in inclusion bodies in the form of misfolded and inactive proteins expressed by prokaryotes such as Escherichia coli back into proteins with correct conformation and bioactivity under appropriate conditions in vitro. It is a key technology for biopharmaceutical companies but a major bottleneck in protein production in prokaryotic expression systems. Leto Labs, having been specializing in protein refolding for many years, has a core team with over ten years’ experience in this technology and rich experience in its industrialization. Our team is summarizing the experience to form an independent technological system of ours.