A quick search on WIPO: https://patentscope.wipo.int/search/en/detail.jsf?docId=US90330323&recNum=6&tab=PCTClaims&maxRec=9&office=&prevFilter=&sortOption=Pub+D

A quick search on WIPO: https://patentscope.wipo.int/search/en/detail.jsf?docId=US90330323&recNum=6&tab=PCTClaims&maxRec=9&office=&prevFilter=&sortOption=Pub+Date+Desc&queryString=FP%3A%28Hierarchical+user+interface+Facebook%29 https://patentscope.wipo.int/search/en/detail.jsf?docId=US90... https://patentscope.wipo.int/search/en/detail.jsf?docId=US196230072&recNum=1&tab=PCTClaims&maxRec=9&office=&prevFilter=&sortOption=Pub+Date+Desc&queryString=FP%3A%28Hierarchical+user+interface+Facebook%29 https://patentscope.wipo.int/search/en/detail.jsf?docId=US19... Query: PA:facebook* AND FP:(Hierarchical user interface) AND CTR:US