Although other firms expressed interest to Kates and Rogers Majestic in using the tubes, issues with acquiring patents prevented him, Rogers Majestic, or the University of Toronto from patenting the tubes anywhere outside Canada until 1955, and the patent application was not accepted in the United States until March 1957, six years after filing.
虽有公司向凯特和Rogers Majestic表示，他们对加法管有兴趣，但他、Rogers Majestic和多伦多大学都受专利限制——该管在1955年前不得在加拿大外使用，而美国专利在申请6年后，到1957年3月才批准。