Computable Contracts by Extracting Obligation Logic Graphs

The emergence of contract specific programming languages has struggled to translate into widespread adoption of computable contracts due largely to high conversion costs. In this work, we present the first system for converting natural language contracts into code through the extraction of key entities, relationships, and formulas into a graph representation called the Obligation Logic Graph (OLG). This approach allows the semantic meaning of contract obligations, including dependencies between obligations, to be captured through the OLG and mapped to code downstream. We also introduce OLG extraction as a new joint entity and relation prediction task for legal contracts, and present the Contract-OLG dataset, consisting of 1,876 contract provisions, 18,597 entities and 18,170 relationships. We perform detailed experiments to understand the capabilities of state-of-the-art Transformer and graph-based models at completing these tasks, and identify where there is currently a significant gap between human expert and machine performance, particularly for relation extraction.