Acts permitted; applications for patents, or registration of trade-marks or copyrights; payment of tax in relation thereto; licenses under enemy owned patent or copyright; statements by licensees; term and cancellation; suits against licensees; restraining infringements; powers of attorney; keeping secret inventions

Nothing contained in this chapter shall be held to make unlawful any of the following acts: If suit is brought as above provided, the court may, at any time, terminate the license, and may, in such event, issue an injunction to restrain the licensee from infringement thereafter, or the court, in case the licensee, prior to suit, shall have made investment of capital based on possession of the license, may continue the license for such period and upon such terms and with such royalties as it shall find to be just and reasonable. In the case of any such patent, trade-mark, print, label, or copyright, conveyed, assigned, transferred, or delivered to the Alien Property Custodian or seized by him, any suit brought under this subsection, within the time limited therein, shall be considered as having been brought by the owner within the meaning of this subsection, in so far as such suit relates to royalties for the period prior to the sale by the Alien Property Custodian of such patent, trade-mark, print, label, or copyright, if brought either by the Alien Property Custodian or by the person who was the owner thereof immediately prior to the date such patent, trade-mark, print, label, or copyright was seized or otherwise acquired by the Alien Property Custodian. When an applicant whose patent is withheld as herein provided and who faithfully obeys the order of the President above referred to shall tender his invention to the Government of the United States for its use, he shall, if he ultimately receives a patent, have the right to sue for compensation in the United States Court of Federal Claims, such right to compensation to begin from the date of the use of the invention by the Government.