RedactionBench

  1. A10 Networks, Inc.

* Corresponding author: sbrynjolfson@a10networks.com

Abstract

As we integrate intelligent systems beside sensitive and private data, we need the ability to redact information to balance utility and safety. In RedactionBench, we pose redaction as a property detection task, thereby transcending any particular taxonomy to discuss frameworks of machine privacy directly. We introduce RedactionBench, a challenging set of 200 diverse documents which have been exhaustively manually annotated for sensitive content, and the R-Score, our metric designed to nullify shallow formatting decisions. In our user study, we demonstrate users have differing privacy expectations and that these differences are concentrated in our contextual units: mean pairwise agreement of mandatory (81.7%), benign (84.1%), and background units (88.7%), are significantly higher than our contextual units (63.8%). We provide comprehensive evaluations of 44 models across a wide range of architectures. While Claude Opus 5.5 scores the highest at 0.832, we demonstrate that a simple base Qwen3.8-27B in the mini-swe-agent harness achieves 0.740, outperforming the strongest PII-specific model, PII-Tracer, by +13.83%.

Interactive R-Score

Select text to redact it; click a redaction to remove it. On mobile, use Randomize redactions to explore different combinations.

Evaluations

Pareto plot of RedactionBench mean R-Score against model size.
Total checkpoint parameter count versus R-Score.

Overall Model Leaderboard

RankModelFamilyR-Score mean
1Claude Opus 5.5General-purpose agent0.832
2Claude Haiku 5.5General-purpose agent0.812
3GPT-6.1 SolGeneral-purpose agent0.750
4Qwen3.8-27B agentGeneral-purpose agent0.740
5GPT-6 LunaGeneral-purpose agent0.686
6Perplexity PII-TracerToken-level0.601
7CobuildX 17MToken-level0.536
8CobuildX 32MToken-level0.535
9OpenAI Privacy FilterToken-level0.533
10CobuildX 68MToken-level0.532
11Qwen3.5-9B agentGeneral-purpose agent0.469
12Fastino GLiNER2 PIISpan-level0.445
13Gretel GLiNER bi-largeSpan-level0.427
14LiquidAI LFM2.5 PIIToken-level0.404
15Qwen3.5-4B agentGeneral-purpose agent0.393
16Bards PII v3Token-level0.390
17HydroxAI PII MaskerToken-level0.387
18OpenMed SuperClinical PIIToken-level0.381
19Jakobhuss Gemma 270MSpecialized generator0.370
20HiveTrace GLiNER Guard uniSpan-level0.341
21B2NER InternLM2.5 7BSpecialized generator0.339
22NVIDIA GLiNER PIISpan-level0.339
23Distil-PII Llama 3BSpecialized generator0.332
24Piiranha v1Token-level0.321
25Knowledgator GLiNER PIISpan-level0.320
26HiveTrace GLiNER Guard biSpan-level0.313
27GLiNER multi-PIISpan-level0.309
28E3-JSI GLiNER PIISpan-level0.302
29Eternis Anonymizer 4BSpecialized generator0.281
30NuExtract 1.5 tinySpecialized generator0.277
31UniNER 7B allSpecialized generator0.270
32DeepakSiloka PII v2.1Token-level0.263
33h2oai DeBERTa PIIToken-level0.238
34Lakshyakh93 DeBERTa PIIToken-level0.238
35NuExtract 2.0 2BSpecialized generator0.238
36Isotonic DistilBERT v2Token-level0.232
37ai4privacy EnglishToken-level0.221
38NuExtract 2.0 4BSpecialized generator0.206
39Tanaos anonymizerToken-level0.201
40GLiNER multi v2.1Span-level0.194
41Distil-PII Llama 1BSpecialized generator0.192
42ai4privacy multilingualToken-level0.180
43Distil-PII Gemma 270MSpecialized generator0.092
44OpenPipe PII-RedactSpecialized generator0.092

† h2oai/deberta_finetuned_pii and lakshyakh93/deberta_finetuned_pii are mirrored uploads of the same checkpoint and produce identical scores.

Data Samples

Citation

@misc{brynjolfsson2026redactionbench,
  title         = {RedactionBench},
  author        = {Brynjólfsson, Sean and Jayakrishnan, Shashvat and Sali, Esha and Purwar, Diptanshu and Aggarwal, Madhav},
  year          = {2026},
  eprint        = {2606.18782},
  archivePrefix = {arXiv},
  primaryClass  = {cs.CL},
  doi           = {10.48550/arXiv.2606.18782},
  url           = {https://arxiv.org/abs/2606.18782}
}