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Patent Tools for
Every Stage

Free utilities built for patent practitioners, in-house IP counsel, and founders. Organized by where you are in the patent lifecycle.

Pre-Grant

Before You File

Search prior art, find classification codes, understand your critical dates, and plan your filing strategy before the application goes in.

4 tools
Free

Patent Search Query Generator

Describe your technology in plain English and get optimized boolean search strings for every major patent database. Add synonyms, edit concepts, copy with one click.

Patent Lens Google Patents USPTO PatFT Espacenet
Free

CPC Code Finder

Search by keyword or technology description to find the right Cooperative Patent Classification codes. Filter by section and copy codes directly for use in searches and applications.

CPC Codes IPC Mapping 50+ Tech Areas
Free

Prior Art Date Calculator

Enter your filing date and get exact prior art cutoff dates under AIA and pre-AIA rules. Includes grace period analysis, § 102 breakdown, and a critical date timeline.

AIA § 102 Pre-AIA Rules Grace Period
Coming Soon

Continuation Strategy Decision Tool

Should you file a continuation, CIP, or divisional? Answer a few questions about your parent application and get a plain-language recommendation with next steps.

Continuation CIP Divisional RCE
Prosecution

From Filing to Grant

Navigate examination — understand claim structure, respond to office actions, track prosecution timelines, and calculate term adjustments.

4 tools
Free

Claim Dependency Mapper

Paste patent claim text and instantly visualize the full dependency tree. See independent claims, dependent chains, and claim depth at a glance. Useful for spotting structural issues before filing.

Dependency Trees Claim Depth Scope Analysis
Free

Claim Strength Analyzer

Paste patent claims and instantly see breadth scores, limitation breakdowns, § 112(f) exposure, functional language flags, and numeric specificity risks — all in your browser, no data sent anywhere.

Breadth Score § 112(f) Functional Language Limitation Count
Coming Soon

Office Action Response Checklist

Select your rejection type — § 102, § 103, § 101, or § 112 — and get a structured checklist of required response elements, common arguments, and strategic considerations.

§ 102 Rejections § 103 Rejections § 101 Eligibility § 112
Coming Soon

Patent Term Adjustment (PTA) Calculator

Calculate USPTO-caused delays and determine how many days of patent term adjustment your patent has earned. Enter prosecution event dates — no Excel download needed.

A/B/C Delays Term Extension USPTO Delays
Post-Grant

After the Patent Issues

Understand what your patent actually covers, manage maintenance deadlines, assess freedom to operate, and build a strategy around your granted IP.

4 tools
Live Data

PTAB Open Analytics

Explore 19,140 IPR proceedings since 2012. Institution rates by petitioner, APJ panel intelligence, settlement timing patterns, and technology area breakdowns — fully interactive.

IPR Proceedings APJ Intelligence Institution Rates
FreeNew

Patent Maintenance Fee Calculator

Enter your issue date and entity type to get exact maintenance fee deadlines at 3.5, 7.5, and 11.5 years — with current fee amounts, grace period windows, and a .ics calendar export. The USPTO sends no reminders; roughly half of all US patents lapse from missed fees.

3.5 / 7.5 / 11.5 Year Fees Small Entity Micro Entity Grace Period
FreePartner Tool

Patent Marking Compliance Tool

Generate correct virtual marking language for your products and patent portfolio. Avoid false marking liability under 35 U.S.C. § 287 and ensure your marking page is AIA-compliant. Built by the same team as PatentSignal.

Virtual Marking § 287 Compliance Patent Notice Portfolio Marking
Coming Soon

Freedom to Operate (FTO) Framework

An interactive step-by-step FTO checklist for startups and in-house counsel. Walk through the key questions — product scope, jurisdiction, patent landscape status — and get a structured risk summary and recommended next steps.

FTO Checklist Risk Assessment Startup-Friendly

Understanding the Three Stages of Patent Work

Patent strategy isn't a single event — it's a process that evolves from the first idea through filing, examination, grant, and ongoing portfolio management. Understanding where you are in that process helps you use the right tools and ask the right questions at the right time.

Pre-Grant: Before the Application

The pre-grant phase covers everything from invention disclosure through filing. This is where you conduct prior art searches to assess patentability, choose the right CPC classification codes, determine your critical dates under AIA or pre-AIA rules, and decide what to claim. Thorough pre-grant work shapes the quality of the claims you file — and therefore the scope of protection you can ultimately obtain.

Prosecution: From Filing to Grant

Once an application is filed, it enters examination at the USPTO. An examiner reviews the claims, searches for prior art, and often issues an Office Action rejecting some or all claims. Responding effectively requires understanding the type of rejection — anticipation (§ 102), obviousness (§ 103), subject matter eligibility (§ 101), or written description and enablement (§ 112) — and crafting a response that overcomes the rejection while preserving the broadest possible claim scope.

Prosecution history is critical: every argument made, every claim amendment, and every concession creates a record that courts use to interpret claim scope after grant.

Post-Grant: After the Patent Issues

A granted patent requires active management. Maintenance fees must be paid at 3.5, 7.5, and 11.5 years or the patent lapses. Claim scope must be understood in light of prosecution history before asserting infringement or licensing. Freedom-to-operate analysis must account for third-party patents. And PTAB proceedings can challenge patent validity long after grant.

Post-grant tools that help patent owners understand what their claims actually cover — not just what the claims say, but what prosecution history allows them to cover — are among the most valuable and most underbuilt in the IP tooling ecosystem.

Frequently Asked Questions

Are these tools free? Do I need to create an account?

Yes — all tools on this page are completely free and require no account. They run in your browser; no data is sent to our servers. For AI-powered deep analysis of specific patents (claim scope, prosecution history, continuation opportunities), see PatentSignal Pro.

When does a US utility patent expire?

A US utility patent filed on or after June 8, 1995 expires 20 years from its earliest effective US filing date, subject to patent term adjustments (PTA) for USPTO-caused delays and patent term extensions (PTE) for regulatory review. Maintenance fees must be paid at 3.5, 7.5, and 11.5 years after grant — roughly half of all US utility patents lapse early due to missed fees.

What is Patent Term Adjustment (PTA)?

Patent Term Adjustment adds days to a patent's term to compensate for USPTO delays during examination. Three types of delay apply: A delays (failure to act within 14 months), B delays (applications pending more than 3 years), and C delays (appeals and secrecy orders). PTA can extend a patent's life by months or years, with significant commercial value in competitive technology fields.

What is a freedom to operate (FTO) analysis?

An FTO analysis determines whether practicing a technology would infringe any in-force patents in a given jurisdiction. FTO is typically conducted before commercializing a product, before a fundraising round, or before an acquisition. Our FTO framework provides a structured checklist to guide you through the key questions.

What is the difference between a continuation and a CIP?

A continuation claims the same subject matter as a parent application to pursue different claim scope. A continuation-in-part (CIP) adds new subject matter not present in the parent — the new matter gets a new priority date. A divisional is filed in response to a restriction requirement, splitting claims directed to distinct inventions.

How do CPC classification codes work?

The Cooperative Patent Classification (CPC) system organizes patents into technology categories in a five-level hierarchy: Section (A–H, Y), Class, Subclass, Group, and Subgroup. Searching by CPC code alongside keywords improves prior art search recall — especially when the same concept is described with different terminology across patents.

Ready to go deeper on a specific patent?

PatentSignal's Signal Engine analyzes claim scope, prosecution history, and continuation opportunities — with reasoning tied to specific claim limitations, not just a relevance score.

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