Leonard Rosenthol is a Senior Principal Scientist with Adobe Systems and serves as their PDF Architect having been involved with PDF technology for almost 30 years. In 2019, he also took on the responsibility of Chief Architect for their Content Authenticity Initiative which led to him chairing the Technical Working Group of the C2PA (Coalition for Content Provenance and Authenticity). Leonard has also served as Senior Standards Representative for Adobe, where he represents Adobe on various international standards bodies including the ISO, W3C, and ETSI. Prior to joining Adobe (for the first time) in 1996, Leonard was the Director of Advanced Technology for Aladdin Systems and responsible for the development of the StuffIt line of products.