The Secretary of the Interior may also have transferable interests in inventions which are not yet patented. In order to protect the patent rights of the Department, for the eventual benefit of the public, a license may be granted with respect to such an invention only if (a) a patent application has been filed thereon; (b) the invention has been assigned to the United States, as represented by the Secretary of the Interior, and the assignment has been recorded in the Patent Office; and (c) the Solicitor of the Department is of the opinion that the issuance of a license will not prejudice the interests of the Government in the invention. Such licenses shall be upon the same terms as licenses relating to patents of the same class, as described in § 6.52.