English

LLM Benchmark Datasets Should Be Contamination-Resistant

Machine Learning 2026-05-20 v1 Artificial Intelligence Cryptography and Security

Abstract

Benchmark datasets are critical for reproducible, reliable, and discriminative evaluation of LLMs. However, recent studies reveal that many benchmark datasets are included in pretraining corpora, i.e., contaminated\textit{contaminated}, which diminishes their value as reliable measures of model generalization. In this paper, we argue that benchmark datasets should be contamination-resistant\textit{contamination-resistant}, i.e., unlearnable\textit{unlearnable}, but support inference\textit{inference}. To accomplish this, we first highlight the wide prevalence of benchmark dataset contamination and outline the properties of contamination-resistant datasets. Second, we highlight how the asymmetry between the inference and training pipelines in the Transformer architecture can be leveraged to support contamination-resistance. Third, we outline mathematical advancements to make these datasets interoperable across various LLM architectures. Based on the above, we call on the community to ensure the reliability of LLM benchmarking by: (i) advancing novel contamination-resistant methodologies, (ii) developing supporting methods and platforms, and (iii) adopting contamination-resistant benchmarks into existing evaluation pipelines.

Keywords

Cite

@article{arxiv.2605.19999,
  title  = {LLM Benchmark Datasets Should Be Contamination-Resistant},
  author = {Ali Al-Lawati and Jason Lucas and Dongwon Lee and Suhang Wang},
  journal= {arXiv preprint arXiv:2605.19999},
  year   = {2026}
}

Comments

Accepted to ICML 2026 Position Paper Track