An applicant for or proprietor of a European patent who, despite taking all due care required by the circumstances, was unable to observe a time limit not specifically excluded by Art. 122(5) may apply to have his rights re-established. The conditions governing this application are fully set out in Art. 122(1) to (6). The provisions of this article might be invoked if e.g. the applicant's working documents have been destroyed by fire and he has been obliged to prepare fresh ones; or if a specialist agency sent him the wrong set of drawings relating to a priority document, and the error was not immediately apparent. In all instances it is necessary for the applicant or proprietor or representative, as the case may be, to supply evidence that he had exercised all due care required by the circumstances and that the delay was caused by unforeseeable factors. Errors of law, however, do not constitute grounds for re-establishment (see e.g. D 6/82, OJ 8/1983, 337, J 31/89 and J 2/02, both not published in OJ).