July 12, 2026
Landmark Patents
Famous inventions, properly explained.
Discover
Beyond search — tools and views.
Start here
Patent Basics
New to patents? The guided learning path — eight short plain-English guides, in the order that makes sense.
Foundations
What Is a Patent?
The whole idea in plain English — what it gives you, what it takes, how long it lasts, what it costs.
The journey
The Patent Process
Idea to granted patent in eight stages — the deadlines that bite at each one, and a free tool for every step.
Tool · §101
Patent Eligibility Check
Walk the Alice/Mayo two-step the courts use — is your software or method even eligible? A reasoned verdict in four questions.
§101 case law
Landmark Eligibility Cases
Alice, Mayo, Diehr, Bilski, Myriad — the ten decisions that draw the patentability line, each holding in plain English.
Subject matter
What Can Be Patented?
Software, algorithms, business methods, genes, recipes, AI — the straight answer for each, with the rule and the case behind it.
§103
Non-Obviousness
The #1 reason patents are rejected — the four Graham factors, the KSR rationales, and the evidence that beats an obviousness rejection.
§102
Novelty & Prior Art
Is it new? The five §102 bars, the first-to-file rule, and how the one-year grace period really works — and where it fails you.
§112
Specification & Disclosure
Teach the invention or lose the claim — written description, enablement, definiteness, and the means-plus-function trap.
Enforcement
Patent Litigation
What really happens in a patent lawsuit — the stages, the Markman hearing, the damages and injunctions at stake, and the defenses.
Intelligence
Patent Landscapes
Who owns patents in AI, Biotech, Semiconductors, and 9 more domains — trends, concentration, and expiring patents in one report.
AI tool
Prior Art Finder
Describe your invention, get the 12 most similar patents ranked by semantic similarity — powered by pgvector embeddings.
Rankings
Most Cited Patents
The patents that built other patents — ranked by forward citation count with industry breakdown.
Public domain
Expiring Soon
Patents entering the public domain in the next 12 months — sorted by citation influence for FTO planning.
Analysis
Concentration Index
HHI scores for 12 technology domains — see which fields are monopolized and which are competitive.
Trends
Filing Trends by Domain
Year-by-year patent filings from 1990 to 2025 for AI, Biotech, Telecom, and 9 other fields.
Head-to-head
Patent Race
Apple vs Samsung, Google vs Microsoft, Pfizer vs Moderna — see how 10 iconic rivalries stack up in patents, citations, and filing history.
Year in review
Patent Year in Review
A decade of annual reports: most-cited patents, top holders, technology domain breakdown, and filing trends — 2015 through 2024.
Cross-domain
Technology Convergence
AI × Pharma. Biotech × Gene Editing. Semiconductors × Telecom. The cross-domain patent clusters at the intersection of two fields.
Public domain
Patent Expiry Calendar
Month-by-month: which significant patents expire in 2025, 2026, 2027, 2028, 2029, and 2030 — ranked by citation influence.
Momentum
Technology Patent Radar
Which domains are accelerating? AI, Gene Editing, and Clean Energy ranked by 3-year filing CAGR and average citations per patent.
IP expiry
Patent Cliff Analysis
Domain-specific patent cliff intelligence: which pharma, biotech, AI, and semiconductor patents expire 2025–2029 and the strategic window they open.
People
Top Inventors
Three ranked lists: most patents filed, highest total citations, and best average citation impact per patent — with domain tags and top invention links.
Synthesis
Innovation Index
A composite score for 12 technology domains from four patent signals: filing velocity, portfolio quality, IP openness (concentration), and public domain opportunity (expiry rate).
Process
Prosecution Timeline
How long does USPTO examination take? Average and median months from filing to grant for all 12 technology domains — with IQR bands and a 2010–present trend.
Claims
Claims Analysis
How many claims do patents actually have? Average, median, P75, and distribution across 12 tech domains — with the highest-claim-count patent in the database.
Daily
Today in Patent History
Every patent filed or granted on this date, across every year in our index.
Rankings
Patent Leaderboards
Most-cited patents, most-litigated patents, top holders, and the most prolific inventors.
Tool
Patent Value Estimator
Heuristic valuation from citations, claims, expiry, litigation, and industry baseline.
Public domain
Just Expired
Patents that recently entered the public domain — newly free to use.
Power tool
Compare 4 Patents
Side-by-side matrix of up to four patents — for portfolio analysis and FTO scoping.
Interactive
Patent Quiz
10 questions on history's most influential patents. Two minutes.
Long-form
550 Years of Invention
Curated timeline from Venice 1474 to USPTO AI guidance — the moments that shaped IP.
Reference
Patent Glossary
Every term you'll encounter, in plain English. 49 individual landing pages.
Explainer
Types of Patents
Utility, design, plant — what each covers, term length, and famous examples.
Reality check
What a Patent Costs
USPTO fees, attorney fees, and maintenance — the real 2026 numbers.
Strategy
Free Patent Search
The best free databases and six tactics for finding prior art that matters.
Definition
Patent Pending Explained
What it really means, the four benefits, and the four things it does NOT do.
Decision
Attorney or DIY?
When to hire a patent attorney vs file yourself — and the dollar threshold.
Legal
Patent Infringement
The two legal tests, three damages categories, and what to do if you receive a demand letter.
Forward-looking
Expiring Soon
Patents that will enter the public domain in the next 365 days — for FTO planning.
Power tool
Claim Diff
Paste two versions of a patent claim, see a word-level redline. For prosecution amendments and IPR prep.
FTO
Claim Chart Tool
Break a claim into elements and apply the all-elements rule. Find the one element that clears your product.
The thesis
What a Patent Doesn't Cover
A patent is a fence, not a flag. The six things it never covers — and how to find the gap.
Monetization
Patent Licensing
Royalty rates by industry, license types, and seven terms that move the deal.
Ownership
Patent Assignment
How patents change hands — USPTO recording + employee invention agreements.
FAQ
Frequently Asked Questions
What is PatentBrief?
PatentBrief is a free tool that explains US patents in plain English — no law degree required. We break down what each patent actually covers, what it doesn't cover, and why it matters.
Is PatentBrief free?
Yes, completely free. You can search patents, read plain-English explanations, compare patents side by side, and export PDF briefs at no cost.
How current is the patent data?
Our database includes patents from the 1970s through recent grants. New patents are added regularly as they're granted by the USPTO.
Can I use PatentBrief for legal advice?
No. PatentBrief is an educational tool, not a law firm. Our explanations help you understand patents, but they don't constitute legal advice. Consult a registered patent attorney for legal guidance.
What does 'what a patent does NOT cover' mean?
Every patent has gaps — things the inventorinventorThe person who actually conceived the invention. Listed on the patent regardless of who owns it.Read more → didn't claimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more →, or claimed too narrowly. PatentBrief highlights these gaps so engineers and founders know exactly what they can and can't build without infringing.