This poster presents preliminary findings of a content analysis of 72 e-journal licenses in terms of perpetual access clauses. This study explored whether perpetual access clauses varied among commercial publishers, society publishers and university presses, whether clauses changed over time, and whether differences existed between consortia and site licenses. Findings showed that the licenses from commercial publisher were more likely to provide perpetual access than licenses from other two types of publishers. We observed an increasing trend in providing perpetual access over time. Consortia licenses were more likely to depend on third-party to obtain perpetual access than site licenses. This study can be helpful for libraries to understand the institutionalization of perpetual access clause in e-journal licenses.