Legal

Legal professionals face a recurring comparison problem: a counterparty returns a revised contract, a regulator issues an updated rule, a client provides a marked-up term sheet. In each case, the attorney's first task is identifying exactly what changed. Traditional side-by-side reading is slow and error-prone — a single missed word change in a liability clause or a quietly altered notice period can have significant consequences. LineDiff eliminates this risk by computing a precise word-level diff between any two contract versions in seconds. Upload two Word documents or PDFs — no Microsoft Word or Adobe required — and every changed clause, sentence, and word is highlighted instantly in a clean split-view or unified interface.

Attorney-client privilege and document confidentiality are professional obligations that extend to every tool in the legal workflow. LineDiff's zero-knowledge client-side encryption was built with this requirement in mind. Document content is encrypted in the browser using the Web Crypto API (NIST P-256 key exchange, AES-GCM symmetric encryption) before any data leaves the client device. LineDiff's server never receives, processes, or stores unencrypted document text — not as a policy matter, but as a technical fact. Each comparison uses a unique per-document encryption key, and share tokens are distributed out-of-band so the sharing mechanism itself does not expose document content. Opposing counsel granted Viewer access sees only what you choose to share; associates with Editor access can annotate without gaining access beyond the specific comparison.

LineDiff's AI Legal domain analysis adds a layer of intelligent triage to the review process. After computing the structural diff, the AI engine identifies critical clause changes, newly added obligations, removed protections, and language patterns that warrant risk flagging. This does not replace legal judgment — it accelerates the judgment process by surfacing the changes most likely to require careful attorney attention. Line-based comments allow attorneys to annotate specific changed lines directly within the comparison, with threaded discussion keeping all feedback anchored to the exact text that triggered it.

PDF export produces a formatted, timestamped comparison report suitable for court records, client deliverables, regulatory audit documentation, and internal files demonstrating due diligence. The exported report captures the full diff in a clean, monospace A4 layout — a professional artifact that can accompany any legal submission or client communication.