Unextractable Protocol Models: Collaborative Training and Inference without Weight Materialization - Long, Alexander; Hewa Koneputugodage, Chamin P; Ajanthan, Thalaiyasingam; Zuo, Yan; Avraham, Gil; Shevchenko, Violetta; Mohaghegh Dolatabadi, Hadi; Ramasinghe, Sameera (Advances in Neural Information Processing Systems, 2025)