As of my last update in September 2023, there is no widely recognized artist by the name of Philippa Marshall with a detailed public biography or significant contributions to the art world that have been documented or acknowledged in major art historical texts, databases, or references. It is possible that Philippa Marshall could be an emerging artist, a local artist, or someone working in a niche area of the art world, whose recognition and documentation might not have reached wider audiences or mainstream art historical discourse yet. The art world is vast and diverse, with many artists working across different mediums, styles, and regions, often gaining recognition at different stages of their careers. If Philippa Marshall is an emerging artist, future developments and contributions to the art world might lead to a more established presence and documented biography. Additionally, the art community continuously evolves, with new artists gaining prominence and recognition for their work and contributions over time.