DAMASHA: Detecting AI in Mixed Adversarial Texts via Segmentation with Human-interpretable Attribution

L D M S Sai Teja, N Siva Gopala Krishna, Ufaq Khan, Muhammad Haris Khan, Atul Mishra


Abstract
In the age of advanced large language models (LLMs), the boundaries between human and AI-generated text are becoming increasingly blurred. We address the challenge of segmenting mixed-authorship text, that is identifying transition points in text where authorship shifts from human to AI or vice-versa, a problem with critical implications for authenticity, trust, and human oversight. We introduce a novel framework, called Info-Mask for mixed authorship detection that integrates stylometric cues, perplexity-driven signals, and structured boundary modeling to accurately segment collaborative human-AI content. To evaluate the robustness of our system against adversarial perturbations, we construct and release an adversarial benchmark dataset Mixed-text Adversarial setting for Segmentation (MAS), designed to probe the limits of existing detectors. Beyond segmentation accuracy, we introduce Human-Interpretable Attribution (HIA) overlays that highlight how stylometric features inform boundary predictions, and we conduct a small-scale human study assessing their usefulness. Across multiple architectures, Info-Mask significantly improves span-level robustness under adversarial conditions, establishing new baselines while revealing remaining challenges. Our findings highlight both the promise and limitations of adversarially robust, interpretable mixed-authorship detection, with implications for trust and oversight in human-AI co-authorship.
Anthology ID:
2026.findings-eacl.326
Volume:
Findings of the Association for Computational Linguistics: EACL 2026
Month:
March
Year:
2026
Address:
Rabat, Morocco
Editors:
Vera Demberg, Kentaro Inui, Lluís Marquez
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
6189–6206
Language:
URL:
https://preview.aclanthology.org/ingest-eacl/2026.findings-eacl.326/
DOI:
Bibkey:
Cite (ACL):
L D M S Sai Teja, N Siva Gopala Krishna, Ufaq Khan, Muhammad Haris Khan, and Atul Mishra. 2026. DAMASHA: Detecting AI in Mixed Adversarial Texts via Segmentation with Human-interpretable Attribution. In Findings of the Association for Computational Linguistics: EACL 2026, pages 6189–6206, Rabat, Morocco. Association for Computational Linguistics.
Cite (Informal):
DAMASHA: Detecting AI in Mixed Adversarial Texts via Segmentation with Human-interpretable Attribution (Teja et al., Findings 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-eacl/2026.findings-eacl.326.pdf
Checklist:
 2026.findings-eacl.326.checklist.pdf