Development of processing methods that lead to the decontamination of tissues and subsequent sterilization as a terminal event can be traced through the patents that have been applied for as each group sought to improve on the safety and efficacy of such tissues. This chapter seeks to introduce the reader to a new source of scientific literature, the patent office, as a means of understanding how processing methods have evolved over time. The chapter is divided into processing using aqueous fluids and using supercritical fluids in that both processing methods are in use today to produce safe and effective allografts for clinical applications.