Board Thread:Questions and Answers/@comment-27802108-20160219071545/@comment-24071195-20160306040355

CCG knows that he fought off the One-Eyed Owl, a SSS-rate Ghoul. Even if she did hold back, which is somewhat unknown, the CCG wouldn't know that. On top of that, as part of the CCG, he has internal knowledge of their operations and procedures, which he could potentially to his advantage in future altercations with them, which in turn makes him a strategic and tactical threat. I wouldn't think it far-fetched for them to label him SSS because of those things alone.