如果你看到别人就一项技术正在申请一个美国专利或已经已经获得一个美国专利，而你觉得你才应该拿到那个专利，可以考虑使用一个像龙虎争霸的程序叫Interference。具体来说，就是你也给美国专利局呈上符合要求的CLAIM(S)，说我要那个专利！专利局一看，如果认定你是龙，别人是虎，你俩要争霸，就会启动Interference程序。说不定专利最后就是你的了呢。

(a) Whenever an application (龙的) is made for a patent which, in the opinion of the Director, would interfere with any pending application(虎的), or with any unexpired patent(虎的), an interference may be declared and the Director shall give notice of such declaration to the applicants, or applicant and patentee, as the case may be. The Board of Patent Appeals and Interferences shall determine questions of priority of the inventions (谁先发明的) and may determine questions of patentability (可专利性). Any final decision, if adverse to the claim of an applicant, shall constitute the final refusal by the Patent and Trademark Office of the claims involved, and the Director may issue a patent to the applicant who is adjudged the prior inventor. A final judgment adverse to a patentee from which no appeal or other review has been or can be taken or had shall constitute cancellation (撤销) of the claims involved in the patent, and notice of such cancellation shall be endorsed on copies of the patent distributed after such cancellation by the Patent and Trademark Office.

当龙虎争霸的内容 same or substantially same，这时候你要特别注意兵贵神速，否则即使你先发明了争霸内容，也会痛失良机。 (b) (1) A claim which is the same as, or for the same or substantially the same subject matter as, a claim of an issued patent may not be made in any application unless such a claim is made prior to one year from the date on which the patent was granted. (2) A claim which is the same as, or for the same or substantially the same subject matter as, a claim of an application published under section 122(b) of this title may be made in an application filed after the application is published only if the claim is made before 1 year after the date on which the application is published.

有可能龙虎达成协议而结束争霸，这时候建议你们及时在美国专利局备案。(c) Any agreement or understanding between parties to an interference, including any collateral agreements referred to therein, made in connection with or in contemplation of the termination of the interference, shall be in writing and a true copy thereof filed in the Patent and Trademark Office before the termination of the interference as between the said parties to the agreement or understanding. If any party filing the same so requests, the copy shall be kept separate from the file of the interference, and made available only to Government agencies on written request, or to any person on a showing of good cause. Failure to file the copy of such agreement or understanding shall render permanently unenforceable such agreement or understanding and any patent of such parties involved in the interference or any patent subsequently issued on any application of such parties so involved. The Director may, however, on a showing of good cause for failure to file within the time prescribed, permit the filing of the agreement or understanding during the six-month period subsequent to the termination of the interference as between the parties to the agreement or understanding. The Director shall give notice to the parties or their attorneys of record, a reasonable time prior to said termination, of the filing requirement of this section. If the Director gives such notice at a later time, irrespective of the right to file such agreement or understanding within the six-month period on a showing of good cause, the parties may file such agreement or understanding within sixty days of the receipt of such notice. Any discretionary action of the Director under this subsection shall be reviewable under section 10 of the Administrative Procedure Act.