Hello Tony, in a piece of general English writing, it would not be necessary to use initial caps for terms like registered holder. In legal documents, such terms are usually defined at the start, lest there be any ambiguity, terms such as lessee, lessor, trustee, registered user, registered holder. Then, in the clauses that follow the introduction, those terms may be used with initial caps as a way of indicating "as defined heretofore". (This is often inconsistent within a document.)
The term legalese is used to describe the (needless) application of legalistic idiom in general usage.