 Insurance policies for professional negligence will frequently require an opinion of counsel before the insurer is required to pay out on any putative claim (sometimes called a QC clause, when it must be an opinion of leading counsel).In commercial transactions, particularly in the context of financing, the lender will require an opinion as to the corporate capacity of the borrower and enforceability of the transaction documents the borrower is intended to enter into.This type of opinion is generally issued by the borrower's counsel or the lender's counsel, depending on the ethical rule governing the issuance of those opinion applicable to the jurisdiction.