PostSig

PostSig is a post-signature operational intelligence platform for legal teams. It uses its LineageAI™ to analyze the full record—agreements, amendments, invoices, and...

Go beyond contract signing with AI that tracks the entire post-signature lifecycle, from amendments to obligations.

PostSig's LineageAI™ provides source-backed operational intelligence on what governs your agreements *now*.

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Pro fromPricing on request

AI AssistantAudit TrailContract AnalysisRisk ManagementData Extraction

8.7 Zekai

Post-Signature Intelligence Layer

AI for Legal

Ease of Use

7.8

Accuracy

9.4

Value

8.4

Time Saving

9.2

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⚡ Quick answer

For legal professionals managing contracts after they are signed, PostSig is the best AI tool for operational intelligence. Unlike general CLMs, it specializes in the post-signature phase, using its LineageAI™ to analyze the complete record, including amendments and invoices. This provides source-backed, auditable answers about current obligations and rights.

CategoryLegal Research & Contract Analysis

Best ForManaging complex, high-value contracts after they are signed

Price FromOn request

FreeNo

DifferentiatorLineageAI™ provides a single source of truth from the entire post-signature record, including amendments and invoices.

ProofNamed an Aragon Research 'Hot Vendor' for its innovative approach to contract performance management.

Rating4.4

📖 About PostSig

PostSig is a post-signature operational intelligence platform for legal teams. It uses its LineageAI™ to analyze the full record—agreements, amendments, invoices, and side letters—to provide source-backed answers on current rights, obligations, and terms.

How It Works

Your workflow, automated

1

Ingest Your Record Family

Connect agreements, amendments, side letters, invoices, and other related records to form a complete intelligence base.

2

Let LineageAI™ Resolve the Truth

The platform automatically orders changes over time, tests operating signals, and determines what terms, rights, and obligations govern now.

3

Act with Source-Backed Answers

Use the LineageAI™ Assistant to ask questions and receive answers with full evidentiary proof, allowing teams to move with conviction.

Real Impact

Before & After

❌ Before

Manually reconstructing contract terms across dozens of amendments and emails to answer urgent business questions.

Hours of manual review

✅ After

Getting instant, source-backed answers about current obligations and rights from a single AI interface.

Minutes to verified answer

Social Proof

Trusted by professionals

Ease of Use

7.8

Accuracy

9.4

Value

8.4

Time Saving

9.2

"PostSig is the only tool I've seen that truly understands the messiness of post-signature contract life. The LineageAI gives us answers with proof, which is exactly what the business needs."

Sarah K., Senior Corporate Counsel · June 2026

"The ability to track invoice variance against amended terms has saved us from significant value leakage. It's a game-changer for contract performance management."

David C., Legal Operations Director · May 2026

"Incredibly powerful for our complex vendor agreements. The learning curve is real, though, and it's so specialized that we still need our old CLM for drafting and e-signature."

Emily T., Contract Manager · June 2026

"Finally, we can stop the manual 'what governs now?' fire drills. The audit trail is fantastic for compliance and showing our work during reviews."

Michael R., Head of Procurement Legal · April 2026

Connects With

Works with your existing stack

PostSig MCP provides governed access to bring answers into approved systems, agents, reports, approvals, and workflows.

Setup complexity: Specialist Platform

PostSig is a post-signature operational intelligence platform for legal teams. It uses its LineageAI™ to analyze the full record—agreements, amendments, invoices, and side letters—to provide source-backed answers on current rights, obligations, and terms.

Who It's For

Why Legal choose this tool

🎯

Built for

This tool is best for legal teams needing to maintain ongoing, operational intelligence on complex contract portfolios after they've been signed.

In-Depth Overview

For legal professionals, the truth of a contract rarely lives in one document. After signing, the record grows with amendments, invoices, side letters, and usage records, making it a nightmare to determine which terms currently govern. This manual reconstruction is slow, error-prone, and introduces significant business risk when decisions are made on incomplete information. PostSig solves this by treating the entire post-signature record as a living source of intelligence. Its core technology, LineageAI™, connects and understands the relationship between all these disparate documents. It reasons across change and time to determine what was amended, superseded, or waived. When you ask a question, PostSig returns a direct answer grounded in the source documents, complete with a full lineage path showing exactly how it arrived at that conclusion. This 'show your work' approach provides an audit-ready trail, giving legal teams the ability to advise the business with conviction, knowing their answers are based on the complete, current truth of the agreement.

Key Use Cases

⚖️

Get instant, source-backed answers on governing terms

In-House Counsel

Instead of manually hunting through amendments and side letters to answer a business question, use the LineageAI™ Assistant to get a verified answer with a clear audit trail of the source documents.

Reduced contract query time from hours to minutes

✓ Pros

Focuses on the critical post-signature phase often overlooked by general CLMs.

LineageAI™ reasons across amendments, invoices, and side letters to find the current truth.

Every answer is source-grounded with a clear, auditable evidence path.

Provides a single source of truth for what governs *now*.

Specialized modules for vendor spend (CPM) and investor rights (IRI).

· Cons

Pricing is not public, suggesting a significant enterprise-level investment.

Highly specialized; may not replace your existing pre-signature CLM.

Appears primarily focused on financial services and large institutions.

Requires a demo, indicating a potentially long sales and onboarding cycle.

⚡ Editorial Verdict

PostSig carves a critical niche in the contract management space by focusing exclusively on the post-signature phase. Its LineageAI™ is powerful for untangling complex histories of amendments and side letters to provide a single source of truth. The main trade-off is its specialization; it's not a pre-signature drafting tool, and its enterprise focus may put it out of reach for smaller legal teams.

Questions & Answers

Frequently asked questions

What is the best AI tool for managing the lifecycle of legal contracts after they are signed? +

PostSig is a leading AI platform for post-signature contract intelligence. It uses LineageAI™ to analyze the entire contract record, including amendments, invoices, and side letters, to determine what terms govern *now*. This provides legal teams with source-backed, auditable answers for managing obligations, rights, and risk.

What does 'post-signature intelligence' mean? +

It refers to the process of understanding and managing a contract after it has been signed. This includes tracking changes from amendments, monitoring obligations, verifying invoices against terms, and understanding how the live agreement evolves over time. PostSig automates this by connecting all related documents into a single source of truth.

How does LineageAI™ work? +

LineageAI™ ingests a 'family' of related records (master agreement, amendments, invoices, etc.) and understands how they relate to each other over time. It determines what was amended, superseded, or changed, allowing it to provide answers based on the most current, in-force terms, complete with an evidence path back to the source documents.

What types of documents can PostSig analyze? +

PostSig is designed to analyze a family of related post-signature records. This includes master agreements, amendments, side letters, invoices, usage records, service orders, approvals, and notices.

Is PostSig suitable for a small law firm or solo practice? +

Based on its feature set and target market (e.g., 'Large Financial Institutions'), PostSig is geared towards larger organizations with complex contract portfolios. Smaller firms with simpler needs may find it overly specialized, and pricing is only available via a demo, suggesting an enterprise-level product.

How does PostSig handle data security and compliance? +

PostSig states it maintains a 'Security, access, and platform trust posture' and notes 'DORA readiness' for financial entities. Its architecture is built around 'governed access' to ensure information is exposed correctly. For specific compliance certifications, you should verify directly with the vendor.

Last reviewed: Reviewed June 2026 — Assessed LineageAI™ capabilities, use cases for legal teams, and overall platform architecture.

Plans & Pricing