(3) A restriction on access to information classified as internal which contains private personal data applies for 75 years as of the receipt or documentation thereof or for 30 years as of the death of the person or, if it is impossible to establish death, for 110 years as of the birth of the person. § 41. Procedure for classification of information as internal (1) Information shall be classified as information intended for internal use by the head of the agency. (11) The head of an agency shall establish, in the list of documents, the series containing documents to which access may be restricted, and indicate the basis therefor provided by this Act or another Act. Establishment of restriction on access to specific documents shall be decided by the head of the agency or, pursuant to the list of documents established by the head of the agency, by a competent employee appointed by the head of the agency, based on the content of the document and the goal of the restriction on access. [RT I 2007, 12, 66 - entry into force 01.01.2008] (2) The person who prepares a document classified as information intended for internal use shall make a notation “ASUTUSESISESEKS KASUTAMISEKS” [“FOR INTERNAL USE”] in capital letters on the document or file of documents, if the medium enables this, or use the corresponding abbreviation AK. The name of the holder of information, the basis of the restriction on access, the final date for application of the restriction on access and the date on which the notation is made shall be added to the notation. (3) A notation shall not be made on documents bearing a notation concerning restriction on access forwarded by other states or international organisations which, pursuant to the State Secrets and Classified Information of Foreign States Act is not deemed to be classified foreign information, except for the invalidation of such restriction if the reason for the restriction on access has ceased to exist. [RT I 2007, 12, 66 - entry into force 01.01.2008] (4) A holder of information who classifies information as internal shall promptly notify the holders of information to whom such information has been forwarded of its classification as internal. [RT I 2007, 12, 66 - entry into force 01.01.2008] § 42. Invalidation of restriction on access (1) A holder of information is required to invalidate a restriction on access if the reasons for establishment thereof cease to exist. (2) If a restriction on access to a document is invalidated, a corresponding notation shall be made on the document. (3) A holder of information shall promptly give notice concerning the invalidation of restriction on access to the holders of information to whom such information has been forwarded. [RT I 2007, 12, 66 - entry into force 01.01.2008] § 43. Protection of internal information (1) A holder of information shall apply administrative and technical measures to ensure that information to which a restriction on access applies cannot be accessed by persons who do not have the right of access. (2) If a restriction on access applies to a document prepared on a computer, the person who prepares the document shall verify that measures have been taken in the agency for the secure processing of data in order to restrict access.