# DOMBA: Double Model Balancing for Access-Controlled Language Models via Minimum-Bounded Aggregation

arXiv: https://arxiv.org/abs/2408.11121 · HTML: https://mlsanity.com/paper/2408.11121/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 12 of its 23 references that are in the map.
- First posted on arXiv 20 Aug 2024.

## Builds on (most cited first, 12 of 12)

- [Training language models to follow instructions with human feedback](https://mlsanity.com/paper/2203.02155/) (2022)
- [Extracting Training Data from Large Language Models](https://mlsanity.com/paper/2012.07805/) (2020)
- [Aligning Books and Movies: Towards Story-like Visual Explanations by Watching Movies and Reading Books](https://mlsanity.com/paper/1506.06724/) (2015)
- [Differentially Private Federated Learning: A Client Level Perspective](https://mlsanity.com/paper/1712.07557/) (2017)
- [Scalable Extraction of Training Data from (Production) Language Models](https://mlsanity.com/paper/2311.17035/) (2023)
- [Differentially Private Fine-tuning of Language Models](https://mlsanity.com/paper/2110.06500/) (2021)
- [Semi-supervised Knowledge Transfer for Deep Learning from Private Training Data](https://mlsanity.com/paper/1610.05755/) (2016)
- [What Does it Mean for a Language Model to Preserve Privacy?](https://mlsanity.com/paper/2202.05520/) (2022)
- [Can Language Models be Instructed to Protect Personal Information?](https://mlsanity.com/paper/2310.02224/) (2023)
- [Submix: Practical Private Prediction for Large-Scale Language Models](https://mlsanity.com/paper/2201.00971/) (2022)
- [Rethinking Privacy in Machine Learning Pipelines from an Information Flow Control Perspective](https://mlsanity.com/paper/2311.15792/) (2023)
- [Information Flow Control in Machine Learning through Modular Model Architecture](https://mlsanity.com/paper/2306.03235/) (2023)

## Built on by (most cited first, 2 of 2)

- [Provably Protecting Fine-Tuned LLMs from Training Data Extraction while Preserving Utility](https://mlsanity.com/paper/2602.00688/) (2026)
- [Chain-of-Authorization: Embedding authorization into large language models](https://mlsanity.com/paper/2603.22869/) (2026)

## Abstract (arXiv)

The utility of large language models (LLMs) depends heavily on the quality and quantity of their training data. Many organizations possess large data corpora that could be leveraged to train or fine-tune LLMs tailored to their specific needs. However, these datasets often come with access restrictions that are based on user privileges and enforced by access control mechanisms. Training LLMs on such datasets could result in exposure of sensitive information to unauthorized users. A straightforward approach for preventing such exposure is to train a separate model for each access level. This, however, may result in low utility models due to the limited amount of training data per model compared to the amount in the entire organizational corpus. Another approach is to train a single LLM on all the data while limiting the exposure of unauthorized information. However, current exposure-limiting methods for LLMs are ineffective for access-controlled data, where sensitive information appears frequently across many training examples. We propose DOMBA - double model balancing - a simple approach for training and deploying LLMs that provides high utility and access-control functionality with security guarantees. DOMBA aggregates the probability distributions of two models, each trained on documents with (potentially many) different access levels, using a "min-bounded" average function (a function that is bounded by the smaller value, e.g., harmonic mean). A detailed mathematical analysis and extensive evaluation show that DOMBA safeguards restricted information while offering utility comparable to non-secure models.
