Private Seeds, Public LLMs: Realistic and Privacy-Preserving Synthetic Data Generation

Qian Ma, Sarah Rajtmajer


Abstract
Large language models (LLMs) have emerged as a powerful tool for synthetic data generation. A particularly important use case is producing synthetic replicas of private text, which requires carefully balancing privacy and utility. We propose Realistic and Privacy-Preserving Synthetic Data Generation (RPSG), which uses private seeds and integrates privacy-preserving strategies, including a formal differential privacy (DP) mechanism in the candidate selection, to generate realistic synthetic data. Comprehensive experiments against state-of-the-art private synthetic data generation methods demonstrate that RPSG achieves high fidelity to private data while providing strong privacy protection.
Anthology ID:
2026.findings-acl.10
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Publisher:
Association for Computational Linguistics
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Pages:
189–210
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.10/
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Cite (ACL):
Qian Ma and Sarah Rajtmajer. 2026. Private Seeds, Public LLMs: Realistic and Privacy-Preserving Synthetic Data Generation. In Findings of the Association for Computational Linguistics: ACL 2026, pages 189–210, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Private Seeds, Public LLMs: Realistic and Privacy-Preserving Synthetic Data Generation (Ma & Rajtmajer, Findings 2026)
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