GenAI content detection Task 1: English and multilingual machine-generated text detection: AI vs. Human

We present the GenAI Content Detection Task 1 - a shared task on binary machine generated text detection, conducted as a part of the GenAI workshop at COLING 2025. The task consists of two subtasks: Monolingual (English) and Multilingual. The shared task attracted many participants: 36 teams made official submissions to the Monolingual subtask during the test phase and 27 teams - to the Multilingual. We provide a comprehensive overview of the data, a summary of the results - including system rankings and performance scores - detailed descriptions of the participating systems, and an in-depth analysis of submissions.1