Scalable multilingual PII annotation for responsible AI in LLMs
Bharti Meena, Joanna Skubisz, Harshit Rajgarhia, Nand Dave, Kiran Ganesh, Shivali Dalmia, Abhishek Mukherji, Vasudevan Sundarababu
TL;DR
This work tackles the challenge of reliably annotating PII across 13 underrepresented locales to support responsible AI in LLMs. It introduces a phased, human-in-the-loop data curation framework that covers ~336 locale-specific PII types and scales to over 40,000 text samples, with a pilot-training-production pipeline and a semi-automatic augmentation approach for HiTL prompts. By measuring inter-annotator agreement and conducting root-cause analyses, the authors achieve notable improvements in $Recall$ and reductions in $FPR$ across locales, yielding high-fidelity datasets for supervised fine-tuning. The framework's analytics-driven design enhances annotation quality and downstream robustness, supporting privacy-preserving LLM deployment under diverse regulatory contexts.
Abstract
As Large Language Models (LLMs) gain wider adoption, ensuring their reliable handling of Personally Identifiable Information (PII) across diverse regulatory contexts has become essential. This work introduces a scalable multilingual data curation framework designed for high-quality PII annotation across 13 underrepresented locales, covering approximately 336 locale-specific PII types. Our phased, human-in-the-loop annotation methodology combines linguistic expertise with rigorous quality assurance, leading to substantial improvements in recall and false positive rates from pilot, training, and production phases. By leveraging inter-annotator agreement metrics and root-cause analysis, the framework systematically uncovers and resolves annotation inconsistencies, resulting in high-fidelity datasets suitable for supervised LLM fine-tuning. Beyond reporting empirical gains, we highlight common annotator challenges in multilingual PII labeling and demonstrate how iterative, analytics-driven pipelines can enhance both annotation quality and downstream model reliability.
