Saved in:
Bibliographic Details
Main Authors: Li, Haodong, Zhang, Jingqi, Cheng, Xiao, Mai, Peihua, Wang, Haoyu, Pang, Yan
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2511.15192
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917095405518848
author Li, Haodong
Zhang, Jingqi
Cheng, Xiao
Mai, Peihua
Wang, Haoyu
Pang, Yan
author_facet Li, Haodong
Zhang, Jingqi
Cheng, Xiao
Mai, Peihua
Wang, Haoyu
Pang, Yan
contents The remarkable language ability of Large Language Models (LLMs) stems from extensive training on vast datasets, often including copyrighted material, which raises serious concerns about unauthorized use. While Membership Inference Attacks (MIAs) offer potential solutions for detecting such violations, existing approaches face critical limitations and challenges due to LLMs' inherent overconfidence, limited access to ground truth training data, and reliance on empirically determined thresholds. We present COPYCHECK, a novel framework that leverages uncertainty signals to detect whether copyrighted content was used in LLM training sets. Our method turns LLM overconfidence from a limitation into an asset by capturing uncertainty patterns that reliably distinguish between ``seen" (training data) and ``unseen" (non-training data) content. COPYCHECK further implements a two-fold strategy: (1) strategic segmentation of files into smaller snippets to reduce dependence on large-scale training data, and (2) uncertainty-guided unsupervised clustering to eliminate the need for empirically tuned thresholds. Experiment results show that COPYCHECK achieves an average balanced accuracy of 90.1% on LLaMA 7b and 91.6% on LLaMA2 7b in detecting seen files. Compared to the SOTA baseline, COPYCHECK achieves over 90% relative improvement, reaching up to 93.8\% balanced accuracy. It further exhibits strong generalizability across architectures, maintaining high performance on GPT-J 6B. This work presents the first application of uncertainty for copyright detection in LLMs, offering practical tools for training data transparency.
format Preprint
id arxiv_https___arxiv_org_abs_2511_15192
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle As If We've Met Before: LLMs Exhibit Certainty in Recognizing Seen Files
Li, Haodong
Zhang, Jingqi
Cheng, Xiao
Mai, Peihua
Wang, Haoyu
Pang, Yan
Artificial Intelligence
The remarkable language ability of Large Language Models (LLMs) stems from extensive training on vast datasets, often including copyrighted material, which raises serious concerns about unauthorized use. While Membership Inference Attacks (MIAs) offer potential solutions for detecting such violations, existing approaches face critical limitations and challenges due to LLMs' inherent overconfidence, limited access to ground truth training data, and reliance on empirically determined thresholds. We present COPYCHECK, a novel framework that leverages uncertainty signals to detect whether copyrighted content was used in LLM training sets. Our method turns LLM overconfidence from a limitation into an asset by capturing uncertainty patterns that reliably distinguish between ``seen" (training data) and ``unseen" (non-training data) content. COPYCHECK further implements a two-fold strategy: (1) strategic segmentation of files into smaller snippets to reduce dependence on large-scale training data, and (2) uncertainty-guided unsupervised clustering to eliminate the need for empirically tuned thresholds. Experiment results show that COPYCHECK achieves an average balanced accuracy of 90.1% on LLaMA 7b and 91.6% on LLaMA2 7b in detecting seen files. Compared to the SOTA baseline, COPYCHECK achieves over 90% relative improvement, reaching up to 93.8\% balanced accuracy. It further exhibits strong generalizability across architectures, maintaining high performance on GPT-J 6B. This work presents the first application of uncertainty for copyright detection in LLMs, offering practical tools for training data transparency.
title As If We've Met Before: LLMs Exhibit Certainty in Recognizing Seen Files
topic Artificial Intelligence
url https://arxiv.org/abs/2511.15192