(1) Where a patent applicant or the person entered in the Register as the proprietor of the patent (section 30 (1)) declares to the German Patent and Trade Mark Office in writing under the terms of section 125a that he or she is willing to allow anyone to use the invention in return for equitable remuneration, the annual renewal fees due in respect of the patent following receipt of the declaration are reduced to one half. The declaration is to be recorded in the Register and published in the Patent Gazette.
(2) The declaration is inadmissible as long as there is an entry in the Register regarding the grant of an exclusive licence (section 30 (4)) or an application is pending before the German Patent and Trade Mark Office for such entry to be made.
(3) Any person who, subsequent to the declaration being entered, wishes to use the invention is to inform the proprietor of the patent of this intention. The information is deemed to have been effected if it has been dispatched by registered letter to the person entered in the Register as the proprietor of the patent or to his or her registered representative or the person authorised to accept service (section 25). The information must indicate how the invention is to be used. Subsequent to the information, the informing party is entitled to effect use in the manner indicated. The informing party is obliged, after the expiry of each calendar quarter, to inform the proprietor of the patent of the use effected and to pay the remuneration for that use. If the informing party does not fulfil this obligation in due time, the person registered as proprietor of the patent may set a reasonable extension of the time for payment and, following expiry without the obligation being fulfilled, may prohibit further use of the invention.
(4) The remuneration is fixed by the Patent Division upon the written request of a party. Sections 46, 47 and 62 apply accordingly to the procedure. The request may be directed against more than one party. When fixing the amount of the remuneration the German Patent and Trade Mark Office may make an order requiring the party opposing the request to bear the costs of the procedure in full or in part.
(5) After the expiry of a period of one year following the last fixing of remuneration, any party affected thereby may apply for its adjustment if, in the meantime, circumstances have arisen or become known which make the remuneration fixed appear obviously inappropriate. In all other cases, subsection (4) applies accordingly.
(6) Where the declaration is made in respect of an application, the provisions of subsections (1) to (5) apply accordingly.
(7) The declaration may be withdrawn in writing under the terms of section 125a vis-à-vis the German Patent and Trade Mark Office at any time, as long as the proprietor of the patent has not yet been informed of any intention to use the invention. The withdrawal takes effect when it is filed. The sum by which the annual renewal fees have been reduced is to be paid within one month following withdrawal of the declaration. If the difference is not paid within the time limit specified in sentence 3, it may still be paid together with the surcharge for late payment before the expiry of a period of a further four months.