qnli question: On what date did the US Government stop legal action? sentence: By the time that the trial wound its way through nine years of legal battles, the U.S. prosecuting attorney had died and the two Bell patents (No. 174,465 dated March 7, 1876 and No. 186,787 dated January 30, 1877) were no longer in effect, although the presiding judges agreed to continue the proceedings due to the case's importance as a "precedent".