For almost two decades now, the PAN lab has been striving to advance the state of the art in text forensics and stylometry through objective evaluation of new and established methods on curated benchmark datasets. In 2026, we organized five shared tasks: (1) Generative AI detection, particularly in mixed and obfuscated authorship scenarios, (2) Text Watermarking, a new task aiming to evaluate inconspicuousness and robustness of text watermarking techniques, (3) Multi-author Writing Style Analysis, a continued task aiming at identifying authorship position changes, (4) Generative Plagiarism Detection, focusing this year on generated text source retrieval, and (5) Reasoning Trajectory Detection, another new task aiming at source identification and safety assessment of generative reasoning chains. PAN 2026 concluded successfully with more than 200 software submissions and 52 notebook papers.