# Clausul

> Clausul is a redline audit tool for legal teams. Upload the version you sent and the draft you got back. Clausul reconciles the two .docx files, surfaces the counterparty's tracked changes alongside any untracked drift (edits the counterparty made without Track Changes on), and classifies what happened to every proposal you sent (accepted, rejected, modified, or unresolved). The reconciliation step is deterministic. The AI writes notes that link to the exact edit so a lawyer can verify every finding before responding.

Pricing: $249 per user per year ($20.75/month equivalent, save $99/year) or $29 per user per month. 14-day free trial, no credit card required. Self-serve signup, no sales calls.

Supported formats: .docx (Microsoft Word 2007 and later) for both inputs and outputs. Output is a real Word file with native `w:ins` / `w:del` tracked changes carrying author name, revision ID, and date stamp. Hyperlinks, bookmarks, fields, footnotes, equations, and embedded images round-trip byte-faithfully.

Security: TLS 1.2+ in transit, AES-256 at rest. Infrastructure hosted in the EU (Germany), GDPR-compliant. Uploaded documents auto-delete after 14 days. Customer documents are never used to train foundation models. AI processing is via the Anthropic API under terms that prohibit training on customer inputs; only parsed clause text is sent, never raw files.

## Frequently Asked Questions

**What does Clausul do?**
Clausul performs a redline audit. Given the version you sent and the draft you received back, it computes what is genuinely different between the two .docx files, regardless of whether the counterparty turned Track Changes on. It also tracks the lifecycle of every proposal you sent across the round (accepted, rejected, modified, or carried forward as unresolved). Output is a real Word file with the counterparty's markup preserved verbatim.

**Why not just use Word's Compare?**
Word's Compare produces a merged redline of every difference. It does not separate the counterparty's tracked changes from the edits they made silently, and it does not tell you what happened to the proposals you sent. Clausul does both, against the same two .docx files Word is comparing.

**What about Litera or Workshare?**
Litera produces high-accuracy redlines and does that well. The differentiation is what comes after. Litera shows a merged redline of every difference. It does not separate the counterparty's tracked changes from the edits they made silently, and it does not classify what happened to each proposal you sent. Clausul does both. If your firm uses Litera, Clausul runs alongside (Litera produces the redline, Clausul audits it). If your firm does not have Litera, Clausul replaces the redline step too, in a browser, without procurement.

**What is an untracked change, and is it really a problem?**
An untracked change is an edit the counterparty made to the document without turning Track Changes on. Deliberate ones are rare. Accidental ones are common (paste from a different draft, accept then edit, forget Track Changes was off for a paragraph). The Clausul check (reject every tracked change in the received draft, then diff against the version you sent) takes seconds. Even when the answer is "no drift," you have stopped trusting the redline alone.

**How accurate is the audit? Could the AI hallucinate findings?**
The reconciliation procedure is deterministic. Clausul rejects every tracked change in the received draft and computes a diff against the version you sent. Anything left over is byte-for-byte different from what you sent. No LLM is involved in that step, so there is nothing for it to miss or invent. The notes that summarize each finding are LLM-written and labeled as such, and every note links to the exact edit so a lawyer can verify it.

**What does the workflow look like in practice?**
Drag two .docx files into the browser. Wait under a minute for most contracts. Walk through findings with j/k, sorted by importance. Filter formatting noise. Export the received .docx with the counterparty's markup preserved verbatim. Mark up your reply in Clausul or in Word.

**What is formatting noise, and what does Clausul do about it?**
When someone reformats a Word document, the underlying XML changes even when no words changed. Line spacing, margins, styles, paragraph marks. Traditional tools report each one. Clausul detects formatting-only edits, groups them so they do not crowd substantive findings, and lets you filter them out or bring them back when you need to verify.

**Does Clausul detect moved text?**
Yes. Moved paragraphs are detected as moves rather than reported as a delete-and-reinsert pair. Edits made inside moved text remain visible.

**Can I edit documents inside Clausul?**
Yes. The Reply product takes one drafting instruction and produces native Word tracked changes across one or more DOCX targets. Each LLM edit lands as a proposal you accept or reject one at a time. Output passes Word's ECMA-376 validation and preserves hyperlinks, bookmarks, fields, footnotes, and embedded images byte-faithfully. If an edit would corrupt a structural element, the runtime rejects the edit before it lands.

**Can I move a redline to a different document?**
Yes. Transfer Redline takes the changes you negotiated in one document and applies them to a structurally different target (counterparty paper, refreshed template, new draft). Matching is semantic by clause content, not positional. Edits with no match are flagged in the result, never silently dropped.

**Can I carry forward negotiated positions into a refreshed draft?**
Yes. Carry-Forward Redlines applies edits from an earlier round to a new base, handling renumbering, template changes, and counterparty paper. Unmatchable edits are surfaced rather than dropped, preserving drafting history.

**Who is Clausul built for?**
Solo, small, and mid-sized law firms (2 to 50 lawyers), in-house legal teams, paralegals, and legal-ops teams who handle counterparty redlines and want a verifiable audit step before responding.

**Is cloud-based document comparison secure enough for legal work?**
Cloud adoption among lawyers is 75%+ overall and higher among solo practitioners. The ABA considers cloud "ethically permissible" with "reasonable efforts" to prevent unauthorized disclosure. Clausul hosts in the EU (Germany), encrypts in transit (TLS 1.2+) and at rest (AES-256), auto-deletes documents after 14 days, supports DPAs, and provides an audit trail of comparisons, exports, and user actions.

**Do you train AI models on customer documents?**
No. AI processing is via the Anthropic API under terms that prohibit using customer inputs for model training. Inputs may be retained by Anthropic for up to 30 days for abuse and safety monitoring, then deleted. No raw document files are sent to the AI provider, only parsed clause text. Raw files and comparison results stay in EU infrastructure.

**What is the difference between a redline and a blackline?**
The same thing. Two names for the marked-up comparison between two contract versions. "Redline" is more common in the US.

**How much does Clausul cost?**
$249 per user per year ($20.75/month equivalent, save $99/year) or $29 per user per month. 14-day free trial, no credit card required. Includes unlimited audits, AI change summaries, exportable redlines, and 14-day auto-delete.

## Core Pages

- [Homepage](https://clausul.com): Redline audit for legal teams. Catch the proposal they silently rejected. Features (untracked-drift detection, proposal-outcome classification, Word-native download, keyboard navigation), pricing, security, FAQ.
- [Compare](https://clausul.com/compare): Compare Word documents and see what actually changed. Upload two .docx files, get a clean redline that surfaces material edits and collapses formatting noise.
- [Reply](https://clausul.com/reply): One drafting instruction, native Word tracked changes across every contract in the bundle. Atomic across documents. Preserves fields, bookmarks, hyperlinks, footnotes, equations.
- [Transfer Redline](https://clausul.com/transfer-redline): Apply edits negotiated in one document to a structurally different target. Semantic matching by clause content, not position.
- [Carry-Forward Redlines](https://clausul.com/carry-forward-redlines): Apply negotiated positions from an earlier draft round to a refreshed base. Handles renumbering and template changes.
- [Legal Blackline](https://clausul.com/legal-blackline): Native Word legal blackline output. Single document with insertions, deletions, and move markup inline.
- [Security](https://clausul.com/security): Where your data goes, what AI sees, what controls you have. EU hosting, GDPR, encryption, retention, DPA, vendor risk questionnaire, audit trail.
- [About](https://clausul.com/about): 200 changes in a redline, three of them matter. Founder story (Andreas Scherman, Stockholm). Four principles behind the tool.
- [Tools](https://clausul.com/tools): Free document comparison tool (no signup, no AI classification, no persistence). Hub for free utilities.
- [Guides](https://clausul.com/guides): Hub for the long-form guides and the blog.

## Guides and Tool Comparisons

- [How to Redline in Word](https://clausul.com/how-to-redline-in-word): Step-by-step guide to Track Changes and Compare Documents in Word, plus the limits that show up in legal work.
- [Contract Redline Software](https://clausul.com/contract-redline-software): Feature comparison of Word Compare, Draftable, Litera, and Clausul for small law firms.
- [Litera Compare Alternative](https://clausul.com/litera-compare): Why small firms (2 to 50 lawyers) may want an alternative to Litera's enterprise approach.
- [Litera Compare Pricing](https://clausul.com/litera-compare-pricing): What firms report paying for Litera Compare ($500 to $1,000+ per user per year reported) and alternatives with transparent pricing.
- [Workshare Compare (now Litera)](https://clausul.com/workshare-compare): Acquisition history. Litera acquired Workshare in November 2019. What changed for users and what the alternatives are.
- [Workshare Compare Alternative](https://clausul.com/workshare-compare-alternative): A Workshare alternative for firms still standardizing on Word after the December 31, 2023 end-of-life date.
- [Draftable Alternative](https://clausul.com/draftable-alternative): Where Draftable's basic diffing falls short for legal work and what semantic comparison adds.
- [compareDocs End of Life](https://clausul.com/comparedocs-end-of-life): Migration guide for compareDocs and Workshare Compare users after the December 31, 2023 end-of-life date.

## Blog

- [Contract Template Drift](https://clausul.com/blog/contract-template-drift): How templates evolve through legal updates and dispute lessons. Auditing the library, detecting drift, comparison as a detection tool.
- [Comparing Terms of Service](https://clausul.com/blog/comparing-terms-of-service): Provisions that change most between ToS versions, what changes mean for users, and how to compare them.
- [Comparing Construction Contracts and Change Orders](https://clausul.com/blog/construction-contract-comparison): Standard forms vs negotiated versions, change order process, pricing structures, cumulative effect of multiple change orders.
- [How to Compare Privacy Policies and DPAs](https://clausul.com/blog/how-to-compare-privacy-policies-and-dpas): Data scope, subprocessors, breach notification, cross-border transfers, and liability across privacy documents and DPAs.
- [Redline Audit Software: How to Audit a Counterparty's Markup](https://clausul.com/blog/redline-audit-software): Long-form definition of audit-and-reply as a contract negotiation discipline. What an audit produces, how it differs from first-pass review, how it feeds reply.
- [Audit vs First-Pass Review](https://clausul.com/blog/audit-vs-first-pass-review): First-pass review takes one document and produces markup. Redline audit takes two documents and produces a verdict on the difference. Why the same tool rarely does both well.
- [How to Reply to a Counterparty Redline Without Losing the Thread](https://clausul.com/blog/how-to-reply-to-counterparty-redline): Accept, reject, counter. Mechanics that go wrong (formatting drift, lost tracked-change metadata, opaque content shape changes) and the discipline that holds up across rounds.
- [What a Redline Audit Catches That a Read-Through Misses](https://clausul.com/blog/what-redline-audit-catches): Six categories of change that read-throughs reliably miss: untracked edits, edits hidden in formatting noise, defined-term cascades, drifted cross-references, moved clauses with stealth edits, and table edits.
- [Comparing Franchise Agreements](https://clausul.com/blog/comparing-franchise-agreements): What changes between the FDD and the final contract. Territory rights, royalty rates, non-competes, renewal terms.
- [How to Compare Loan Agreements and Credit Facilities](https://clausul.com/blog/how-to-compare-loan-agreements): A single-number change to a financial covenant, SOFR spread, default trigger, or negative covenant can cost millions.
- [How to Compare Insurance Policies](https://clausul.com/blog/how-to-compare-insurance-policies): Renewals, endorsements, and coverage gaps. Insurers change policy language; changes to exclusions or definitions can eliminate coverage without changing the premium.
- [Comparing Licensing Agreements](https://clausul.com/blog/comparing-licensing-agreements): IP, software, and content licenses. Single-word changes can eliminate the commercial value of a license. Scope, royalties, termination, survival.
- [Managing Multi-Round Contract Negotiations](https://clausul.com/blog/managing-multi-round-contract-negotiations): 5, 10, 15+ round negotiations create version control challenges manual review cannot handle. Strategies, the lost-change problem, a practical workflow.
- [How to Review a Commercial Real Estate Lease Redline](https://clausul.com/blog/commercial-real-estate-lease-redline): 50 to 100+ pages of interconnected financial terms, operating expense definitions, and construction exhibits. Starting with financial impact and catching what matters in the exhibits.
- [Document Comparison Security: What Lawyers Should Ask Before Uploading](https://clausul.com/blog/document-comparison-security): Seven questions on data retention, encryption, access controls, ethical obligations, and a security evaluation checklist.
- [How to Compare a Scanned PDF Against a Word Contract](https://clausul.com/blog/compare-scanned-pdf-to-word): OCR-first workflow. Quality issues, artifacts to watch for, limitations to understand.
- [Comparing Settlement Agreements](https://clausul.com/blog/comparing-settlement-agreements): The clauses that change at the last minute, what those changes mean, and how to compare drafts when time is short.
- [Why Track Changes Gets Turned Off (And What to Do About It)](https://clausul.com/blog/track-changes-turned-off): Why Track Changes gets turned off mid-negotiation more often than lawyers realize. How to detect it. Why independent comparison is the standard.
- [The Paralegal's Guide to Producing Clean Redlines](https://clausul.com/blog/producing-clean-redlines): Version verification, formatting normalization, comparison settings, cleanup, quality checks.
- [What Is a Legal Blackline?](https://clausul.com/blog/what-is-legal-blackline): What the term means, how to produce one in Word, what Word gets right, and when to reach for a standalone tool.
- [How to Justify a Document Comparison Tool to Your Managing Partner](https://clausul.com/blog/justify-document-comparison-tool): Business case for ROI. Time savings, risk reduction, client service. Concrete numbers and a framework.
- [Don't Trust the Counterparty's Redline: Verify Before You Rely On It](https://clausul.com/blog/verify-counterparty-redlines): Tracked changes show what the other side flagged. They cannot show what was never tracked. Why untracked edits happen, how they hide, the verification step that catches them.
- [iManage Compare vs Standalone Comparison Tools](https://clausul.com/blog/imanage-compare-vs-standalone-tools): Where iManage Compare works well for DMS-resident documents, where it falls short, when standalone tools complement it.
- [Combine vs Compare vs Consolidate](https://clausul.com/blog/combine-compare-consolidate-redline-workflows): The three redline workflows legal teams confuse. Honest breakdown of each, when to use which, what Clausul supports.
- [DiffChecker vs Word Compare vs Clausul](https://clausul.com/blog/diffchecker-vs-word-compare-vs-clausul): A three-way comparison. Three tiers of document comparison, real scenarios, a decision framework.
- [Deleted Words Matter: What Courts Do With Drafting History](https://clausul.com/blog/deleted-words-matter-drafting-history): Delaware Chancery calls drafting history "especially revealing" when interpreting ambiguous provisions. Why deletions have interpretive weight.
- [Workshare vs Clausul: What Changed After the Litera Acquisition](https://clausul.com/blog/workshare-vs-clausul): What changed for Workshare users, what they tend to look for next, how Clausul compares as a standalone alternative.
- [How to Transfer Tracked Changes to Another Document](https://clausul.com/blog/how-to-transfer-tracked-changes-to-another-document): When the counterparty switches templates or your template gets updated mid-negotiation, how to transfer redline edits without redoing them by hand.
- [Contract Comparison for Procurement Teams](https://clausul.com/blog/contract-comparison-for-procurement-teams): Pricing, payment terms, SLAs, exit costs, and the procurement-legal handoff. Vendor renewals, competitive proposals.
- [Document Comparison for Paralegals: A Practical Workflow](https://clausul.com/blog/document-comparison-for-paralegals): Version identification, running comparisons, reviewing output, producing clean redlines, managing multi-round negotiations.
- [Document Comparison for In-House Counsel](https://clausul.com/blog/document-comparison-for-in-house-counsel): Template governance, playbook verification, cross-contract consistency. A workflow for catching what outside counsel miss.
- [Comparing Purchase Orders and Supply Agreements](https://clausul.com/blog/comparing-purchase-orders-and-supply-agreements): How POs and supply agreements interact and conflict. Battle of the forms. Clauses that change most.
- [How to Compare SaaS Subscription Agreements](https://clausul.com/blog/how-to-compare-saas-agreements): SaaS agreements shift risk, increase costs, and limit data portability between drafts and renewals. Clauses that matter and vendor tactics to watch for.
- [How to Compare Lease Agreements](https://clausul.com/blog/how-to-compare-lease-agreements): Commercial and residential. Financial schedules, construction exhibits, long-term obligations. Lease-type-specific watch lists.
- [How to Create a Redline Comparison in Word (Step by Step)](https://clausul.com/blog/how-to-create-redline-comparison-in-word): Step-by-step guide to Word's Compare Documents. Settings, reading the output, common problems, when you need more.
- [Litera Compare vs Clausul](https://clausul.com/blog/litera-compare-vs-clausul): Direct comparison. Pricing, features, integrations, which tool fits which firm.
- [What Is Document Redlining?](https://clausul.com/blog/what-is-document-redlining): What redlining involves, where the practice came from, how the process works, where modern tools fall short.
- [Contract Redlining Best Practices](https://clausul.com/blog/contract-redlining-best-practices): A structured workflow. Preparation, comparison, structured review, common mistakes, when to escalate.
- [How to Compare Employment Agreements](https://clausul.com/blog/how-to-compare-employment-agreements): What HR and legal teams miss. Clauses that change most, what they mean, how to catch them.
- [The True Cost of Free Document Comparison](https://clausul.com/blog/true-cost-of-free-document-comparison): Free tools have real costs. Missed changes, security gaps, workflow friction.
- [Why Enterprise Comparison Tools Don't Fit Small Law Firms](https://clausul.com/blog/enterprise-comparison-tools-vs-small-firms): Litera and other enterprise tools are built for Am Law 100 firms. Why they do not work for small firms.
- [How to Review an MSA Redline](https://clausul.com/blog/how-to-review-msa-redline): Master services agreements are long, dense, and full of interdependent clauses. A structured approach.
- [Legal Document Version Control: Beyond Track Changes and File Names](https://clausul.com/blog/legal-document-version-control): File naming and Track Changes are not version control. What actual version control looks like for contract negotiation.
- [Comparing NDAs: The Clauses That Change Most Often](https://clausul.com/blog/comparing-ndas-clauses-that-change-most): NDAs look simple until you compare versions. Seven clauses that change most often.
- [What Happens When You Miss a Change in a Contract](https://clausul.com/blog/what-happens-when-you-miss-a-contract-change): Financial exposure, broken obligations, malpractice risk. Real patterns of how changes get missed and how to prevent it.
- [5 Questions to Ask Before Buying Document Comparison Software](https://clausul.com/blog/questions-before-buying-comparison-software): What to evaluate. Five questions that separate legal-specific tools from generic diff utilities.
- [Cross-References and Section Renumbering](https://clausul.com/blog/cross-references-and-section-renumbering): When sections renumber, cross-references can break silently. How it happens, why tools miss it, how to audit for it.
- [Moved Clauses in Contract Redlines](https://clausul.com/blog/moved-clauses-in-contract-redlines): When a clause is moved, most tools show a deletion and an insertion. How to spot moves and what tools get wrong.
- [Table Changes in Contracts](https://clausul.com/blog/table-changes-in-contracts): Pricing tables, SLA matrices, disclosure schedules. The most financial risk per page, and where comparison tools are weakest.
- [How Formatting Changes Hide Real Edits](https://clausul.com/blog/how-formatting-changes-hide-real-edits): Formatting noise is the most common reason lawyers miss important changes in contract comparisons.
- [Contract Review Checklist](https://clausul.com/blog/contract-review-checklist): A priority-ordered checklist for reviewing contract comparisons. What a comparison tool shows vs what a checklist catches.
- [How to Redline in Google Docs (And Why Lawyers Outgrow It)](https://clausul.com/blog/how-to-redline-in-google-docs): Suggesting mode works for simple edits. For tables, formatting detection, and change classification, a dedicated tool is needed.
- [Redline vs Blackline: What's the Difference?](https://clausul.com/blog/redline-vs-blackline): The same thing. Two names for the marked-up comparison. Where the terms come from and when the distinction matters.
- [How Defined Term Changes Cascade Through Contracts](https://clausul.com/blog/how-defined-term-changes-cascade): A single edit to a defined term can change the meaning of dozens of clauses. How cascades work and why tools miss them.
- [Can You Trust Track Changes?](https://clausul.com/blog/can-you-trust-track-changes): Track Changes records what happened while tracking was on. Independent comparison shows what actually changed. Why experienced lawyers use both.
- [Always Compare the Final Clean Copy Before Signing](https://clausul.com/blog/always-compare-final-clean-copy): The clean copy for execution should match the agreed version. Sometimes it does not. A two-minute comparison catches the difference.
- [What to Look For When Comparing Contracts by Type](https://clausul.com/blog/what-to-look-for-comparing-contracts-by-type): Different contracts need different priorities. NDAs, MSAs, employment agreements, and purchase agreements.
- [DiffChecker for Legal Documents: When Free Comparison Falls Short](https://clausul.com/blog/diffchecker-for-legal-documents): DiffChecker is fast and free but compares text, not documents. Where it works, where it fails, what to use instead.
- [Draftable vs Clausul](https://clausul.com/blog/draftable-vs-clausul): Honest side-by-side comparison. Four scenarios, a feature table, a decision framework.
- [What Is Semantic Document Comparison?](https://clausul.com/blog/what-is-semantic-document-comparison): How semantic comparison classifies changes by meaning, six practical examples, how it works under the hood, honest limits.
- [AI Document Comparison vs Manual Redlining](https://clausul.com/blog/ai-vs-manual-redlining): When AI comparison actually helps and when manual redlining is fine. Honest about the hype.
- [What Is Contract Redlining? (And Where Most Tools Get It Wrong)](https://clausul.com/blog/what-is-contract-redlining): What redlining involves in daily legal practice. Where standard tools fall short.
- [Why Word Compare Fails Legal Contracts](https://clausul.com/blog/why-word-compare-fails-legal-contracts): Five specific failure modes and what to look for in an alternative.
- [How to Spot Material Contract Changes (and Ignore Redline Noise)](https://clausul.com/blog/material-contract-changes-vs-formatting-noise): A 5-minute workflow for separating material edits from formatting noise.
- [Best Contract Comparison Tool for Small Law Firms](https://clausul.com/blog/contract-comparison-for-small-law-firms): Which tool works for firms with 5 to 50 lawyers. Pricing, features, when the free option is enough.
- [How to Compare Contracts Efficiently](https://clausul.com/blog/how-to-compare-contracts-efficiently): A step-by-step workflow. Setup, triage, common mistakes, output.
- [Document Comparison Guide for Legal Teams](https://clausul.com/blog/document-comparison-for-legal-teams): Comprehensive guide. From Word's built-in compare to AI-powered tools, how to pick what works for the firm.
- [Why Document Comparison Matters for Lawyers](https://clausul.com/blog/why-document-comparison-matters): Missing a single changed clause can cost millions. Why reliable comparison is not optional for legal work.