Hepatopetal denotes flow of blood towards the liver, which is the normal direction of blood flow through the portal vein. The purpose of this guide is to provide you with basic information about filing a utility patent application with the USPTO.Interestingly, hepatopetal flow (systemic to portal shunting) may be seen in cases of IVC thrombosis. The first step in the NIH patent process is to report a discovery through filling an EIR form and submitting it to TTC for handling and processing. A stepbystep overview of a patent application and maintenance process. The five stages of a patent process.