For the purpose of this Regulation:
(a) "document" shall mean any content whatever its medium (written on paper or stored in electronic form or as a sound, visual or audiovisual recording) concerning a matter relating to the policies, activities and decisions falling within the institution's sphere of responsibility;
(b) "third party" shall mean any natural or legal person, or any entity outside the institution concerned, including the Member States, other Community or non-Community institutions and bodies and third countries.