1. A design verification apparatus for verifying a design of a circuit diagram designed by utilizing circuit data that is data for the designed circuit diagram, the design verification apparatus comprising: a determination unit for, by searching a second component to be connected to a first component in a circuit diagram, based on information obtained from circuit data, determining whether or not the second component is a logically transparent component whose input and output are logically identical in value, and when the second component is a logically transparent component, further searching a component to be connected to the second component, creating data, on a logically transparent net, that is information on a net in which components other than the logically transparent components are connected with one another and then creating design-verification data that is obtained by adding the data on a logically transparent net to the circuit data; a storage unit for storing the design-verification data; and a verification unit for performing design verification, by utilizing design-verification data stored in the storage unit and tracing components connected to the logically transparent net.