Party Extraction from Legal Contract Using Contextualized Span Representations of Parties

Sanjeepan Sivapiran, Charangan Vasantharajan, Uthayasanker Thayasivam


Abstract
Extracting legal entities from legal documents, particularly legal parties in contract documents, poses a significant challenge for legal assistive software. Many existing party extraction systems tend to generate numerous false positives due to the complex structure of the legal text. In this study, we present a novel and accurate method for extracting parties from legal contract documents by leveraging contextual span representations. To facilitate our approach, we have curated a large-scale dataset comprising 1000 contract documents with party annotations. Our method incorporates several enhancements to the SQuAD 2.0 question-answering system, specifically tailored to handle the intricate nature of the legal text. These enhancements include modifications to the activation function, an increased number of encoder layers, and the addition of normalization and dropout layers stacked on top of the output encoder layer. Baseline experiments reveal that our model, fine-tuned on our dataset, outperforms the current state-of-the-art model. Furthermore, we explore various combinations of the aforementioned techniques to further enhance the accuracy of our method. By employing a hybrid approach that combines 24 encoder layers with normalization and dropout layers, we achieve the best results, exhibiting an exact match score of 0.942 (+6.2% improvement).
Anthology ID:
2023.ranlp-1.116
Volume:
Proceedings of the 14th International Conference on Recent Advances in Natural Language Processing
Month:
September
Year:
2023
Address:
Varna, Bulgaria
Editors:
Ruslan Mitkov, Galia Angelova
Venue:
RANLP
SIG:
Publisher:
INCOMA Ltd., Shoumen, Bulgaria
Note:
Pages:
1085–1094
Language:
URL:
https://aclanthology.org/2023.ranlp-1.116
DOI:
Bibkey:
Cite (ACL):
Sanjeepan Sivapiran, Charangan Vasantharajan, and Uthayasanker Thayasivam. 2023. Party Extraction from Legal Contract Using Contextualized Span Representations of Parties. In Proceedings of the 14th International Conference on Recent Advances in Natural Language Processing, pages 1085–1094, Varna, Bulgaria. INCOMA Ltd., Shoumen, Bulgaria.
Cite (Informal):
Party Extraction from Legal Contract Using Contextualized Span Representations of Parties (Sivapiran et al., RANLP 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.ranlp-1.116.pdf