Royal Sign Manual

The royal sign-manual is the signature of the sovereign, by the affixing of which the monarch expresses his or her pleasure either by order, commission, or warrant. A sign-manual warrant may be either an executive act—for example, an appointment to an office—or an authority for affixing the Great Seal of the pertinent realm. The sign-manual is also used to give power to make and ratify treaties. "Sign manual", with or without hyphen, is an old term for a hand-written signature in general. It is also referred to as "sign manual and signet".

The royal sign-manual usually consists of the sovereign's regnal name (without number, if otherwise used), followed by the letter R for Rex (King) or Regina (Queen). Thus, the signs-manual of both Elizabeth I and Elizabeth II read Elizabeth R. When the British monarch was also Emperor or Empress of India, the sign manual ended with R I, for Rex Imperator or Regina Imperatrix (King-Emperor/Queen-Empress).

When the future George IV, then the Prince of Wales, became regent on behalf of his incapacitated father, George III, the Regency Act 1811 expressly directed that the prince should sign "George P R", the initials in this case standing for Princeps Regens.

Some letters patent are not signed by the monarch in person. Instead, the monarch signs a warrant authorizing the preparation of the letters patent (traditionally written in ceremonial calligraphy on vellum) and approving the draft text of the letters patent. Then, once the letters patent are prepared, they are sealed with the Great Seal without the need for the signature of the monarch, because royal authority for issuing the letters patent had already been given by means of the warrant. Those letters patent finish with the words "By warrant under the King/Queen's Sign Manual," to signify that they do not bear the sign-manual themselves, having already been approved by warrant signed by the sovereign.

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