In the automated design of integrated circuits, signoff (also written as sign-off) checks is the collective name given to a series of verification steps that the design must pass before it can be taped out. This implies an iterative process involving incremental fixes across the board using one or more check types, and then retesting the design. There are two types of sign-off's: front-end sign-off and back-end sign-off. After back-end sign-off, the chip goes to fabrication. After listing out all the features in the specification, the verification engineer will write coverage for those features to identify bugs, and send back the RTL design to the designer. Bugs, or defects, can include issues like missing features (comparing the layout to the specification), errors in design (typo and functional errors), etc. When the coverage reaches a maximum percentage then the verification team will sign it off. By using a methodology like UVM, OVM, or VMM, the verification team develops a reusable environment. Nowadays, UVM is more popular than others.