Patentable means an invention meets every legal condition for a patent to be granted and to survive challenge.

Seven questions answer it, and they are worth asking in a specific order — cheapest and most decisive first.

Most inventions fail on question three, which is also the one you can answer yourself in an afternoon for nothing.

Work down the list and stop at the first failure. There is no point assessing enablement on something already described in a 2015 patent.

Why order matters

Running the questions out of order wastes money and occasionally destroys rights.

Doing this first Costs you
Drafting claims Effort on something already described
Commissioning a professional search Money the free search would have saved
Showing it to a manufacturer Foreign rights, if unfiled
Building a prototype Time, if the concept is anticipated
Assessing commercial value Analysis of something unpatentable
The free prior art search Nothing — and it answers the most likely failure

The disclosure question is the only one with no remedy, which is an argument for checking it before any conversation with a third party rather than at question six.

Everything else can be reordered without loss. Only the search-first rule and the disclose-nothing rule are strict.

The test in order

# Question Cost to answer Failure rate
1 Is it in a statutory category? Minutes Very low
2 Is a judicial exception in play? Hours High for software and diagnostics
3 Has anything disclosed it already? Free — an afternoon Highest
4 Would it have been obvious? Harder High
5 Can you describe it well enough to build? Your own judgement Moderate
6 Have you disclosed it publicly? Minutes Fatal if outside the window
7 Is it worth the cost? An hour The one most often skipped

Question three first if you want one answer. It eliminates more inventions than everything else combined and costs only time.

Question six is the one that cannot be fixed. Everything else has a remedy.

1. Is it in a statutory category?

Category Covers
Process A series of steps
Machine A device with interacting parts
Article of manufacture A made thing
Composition of matter Chemical combinations

Almost everything physical passes. Improvements count too — a new and useful improvement to an existing machine is squarely within §101.

If it is a physical thing or a series of steps, move on. This question rarely stops anything.

2. Is a judicial exception in play?

Exception Fields most affected
Abstract ideas Software, business methods, fintech
Laws of nature Diagnostics, personalised medicine
Natural phenomena Biotechnology, isolated compounds

Only assess this seriously if you are in one of those fields. For mechanical and most chemical inventions it is not the battleground.

The drafting test that predicts the outcome: does the claim recite what is achieved or how it is achieved?

Claim shape Prospects
"A system that predicts availability" Poor — recites a result
"Partitioning the dataset by time window, computing X using [specified technique]" Better — recites a mechanism

If your description is a result, rewrite it as a mechanism before going further. See what can be patented.

3. Has anything disclosed it already?

The decisive question, and free to answer.

Search Where
Full text, worldwide Google Patents
Authoritative US records USPTO Patent Public Search
Families and foreign equivalents Espacenet
Products on sale Ordinary shopping and trade searches
Non-patent literature Journals, conferences, manuals

Search by function, in five different vocabularies. You call it a flow stabiliser; the reference calls it a damping baffle. Write down five ways a stranger would describe what it does and search all of them.

A product on sale is prior art whether or not anyone patented it, so market searching matters as much as database searching.

Prior art is anything public, anywhere, in any language, whether or not anyone read it. See prior art definition.

4. Would it have been obvious?

Harder, because hindsight makes everything look obvious once you know the answer.

Ask Suggests non-obvious
Did others try and fail? Yes
Was there a long-felt need? Yes
Were the results unexpected? Yes
Did the combination require a reason to combine? Yes
Is it just two known things put together? No — likely obvious

Document your evidence now. Failed competitor attempts, unexpected results and long-felt need are §103 evidence, and they are far easier to record today than to reconstruct in year six.

A nexus is required. The evidence must tie to the claimed feature, not to marketing or price.

5. Can you describe it well enough to build?

Test Standard
Could an engineer in the field build it from your description? Enablement
Without solving problems you have not addressed? Without undue experimentation
Do you describe alternatives, not just your version? Supports broader claims
Is every claim term defined or clear? Definiteness

No prototype is needed. A sufficiently detailed written description counts as constructive reduction to practice, and many patents issue on things never built.

Describing alternatives is where breadth comes from. New matter cannot be added after filing, so a variation not written on day one is permanently unavailable.

6. Have you disclosed it publicly?

The question that cannot be un-answered.

What you did US position Rest of world
Nothing public Clear Clear
Told someone under an NDA Clear Clear
Conference talk, demo, crowdfunding page 12-month clock running Rights likely lost
Offered for sale, even confidentially 12-month clock running Rights likely lost
Public more than 12 months ago US rights gone too Gone

The grace period is personal and US-only. It removes your own disclosure from the art against your own application, and almost nowhere else provides an equivalent.

A confidential sale still counts. Following Helsinn, a commercial offer for sale triggers the bar even where the invention details stayed secret.

If anything is public, file now and assume foreign rights are gone.

The alternatives if it is not patentable

Route Gives you
Trade secret No expiry, no disclosure — while it stays secret
Defensive publication Stops anyone else patenting it, very cheaply
Trademark on the name Indefinite, and separate from the invention
Copyright in software or content Automatic, long term
Design patent on appearance Cheaper and faster than utility
First-mover execution No legal protection, real commercial value

Trade secret is the genuine alternative for process inventions. If a competitor could not tell from the product that you use the technique, secrecy can outlast any patent.

Filing forecloses secrecy permanently, because publication at eighteen months destroys it whether or not the patent grants. That is the one IP decision that cannot be revisited. See can you patent something and make it free.

7. Is it worth the cost?

Patentability is a legal test with no commercial component, which is why this question is separate and last.

Cost Amount
Provisional application ~$60–$300 in fees, plus preparation
Non-provisional to grant $8,000–$20,000
Maintenance fees, large entity $14,470
Maintenance fees, micro entity $2,894
Ipiry Patent Survival Curve v1.0 Rate
Survive the 3.5-year fee (2022 cohort) 85.8%
Survive the 7.5-year fee (2018 cohort) 64.6%
Reach full term (2014 cohort) 41.4%
Abandoned before full term 58.6%

Computed from 27,273,654 USPTO maintenance fee records covering 8,262,336 US utility patents — see the patent survival curve.

Every one of those abandoned patents passed the patentability test. Nearly three in five were later judged not worth the fee, which is what the gap between patentable and worthwhile looks like at scale.

Ask whether a competitor would practise the invention. That question predicts value better than any assessment of cleverness.

The four statutory conditions behind the test

The seven questions map onto four conditions in the statute.

Question Condition Statute
1, 2 Eligible subject matter §101
3 Novelty §102
4 Non-obviousness §103
5 Adequate disclosure §112
6 Timing of your own disclosure §102(b) grace period
7 Not a legal condition at all

All four legal conditions must hold simultaneously. Strength in three does not compensate for failure in the fourth.

Question seven is not in the statute. Commercial worth has no bearing on patentability, which is exactly why it has to be asked separately. See the meaning of patentable.

What to do at each failure

Failed at Remedy
1 — Category Rare; reframe as a process or machine
2 — Judicial exception Rewrite the claim as a mechanism, not a result
3 — Anticipated Reformulate around what the art did not do
4 — Obvious Gather secondary-consideration evidence, or narrow
5 — Enablement Gather the missing data before filing
6 — Public disclosure US: file within 12 months. Foreign: gone
7 — Not worth it Stop, and consider trade secret or publication

Failing question three is usually a reformulation, not an ending. The close prior art shows what has been tried and where it fell short, and the unsolved problem is frequently visible in the failures documented there. See invention ideas.

Failing question seven has good alternatives. A trade secret lasts as long as secrecy does and requires no disclosure; defensive publication stops anyone else patenting it for very little money.

Worked example: running the test

A modification to a bicycle lock that alerts on tampering.

# Question Result
1 Statutory category Pass — a machine
2 Judicial exception Concern — "detect and notify" is a result
3 Prior art search, 1 hour Fail — 40+ patents, products on sale

Stopped at question three, for nothing but an hour.

The reformulation

The search also showed what the existing products get wrong — false alarms from wind and passing traffic, severe enough that reviews report users disabling alerts.

# Question Result on the reformulation
1 Category Pass
2 Exception Pass — a specific signal-processing mechanism
3 Prior art Requires a fresh search on the signal processing
4 Obviousness Turns on whether applying it here was obvious
5 Enablement Needs real measurement data
6 Disclosure Nothing public — clear
7 Worth it Depends on whether anyone would practise it

The invention came out of the search, not before it. That is the ordinary pattern and the reason question three is not merely a filter.

Who can answer which question

Question You can answer Needs help
1 — Category Yes
2 — Judicial exception Partly Software and diagnostics
3 — Prior art Yes — free search Professional search before filing
4 — Obviousness Partly Hindsight makes it hard
5 — Enablement Yes
6 — Disclosure timing Yes
7 — Worth it Yes

Five of seven you can answer yourself. Obviousness is the hardest, because hindsight makes everything look obvious once you know the answer, and assessing your own invention is where that bias is strongest.

Subject-matter eligibility is worth professional input in affected fields. The Alice framework is applied in ways that are difficult to predict from the outside.

What changes the answer over time

Change Effect
Someone else publishes Novelty may be lost
You disclose publicly Grace period starts; foreign rights go
An unpublished application publishes Becomes prior art from its filing date
Case law shifts on eligibility §101 answer can move
You develop the invention further May become patentable
The market changes Question seven changes

Patentability is assessed at a point in time and the ground moves. An assessment from two years ago says nothing about today, because applications publish continuously and each becomes prior art from its own filing date.

Which argues for filing once the answer is yes. Waiting to be more certain allows the certainty to expire.

Is it patentable: the checklist

  1. Search the prior art first, before assessing anything else. It is free and it eliminates most inventions.
  2. Search by function in five vocabularies, not by your name for the thing.
  3. Search products on sale too, since they are prior art whether or not patented.
  4. Assess subject matter only if you are in software, business methods or diagnostics.
  5. Check whether your description recites a mechanism or a result. Rewrite if it is a result.
  6. Read the close prior art properly. The reformulation is usually in it.
  7. Document failed attempts and unexpected results now, as §103 evidence.
  8. Test enablement honestly — could an engineer build it from your description alone?
  9. Check every public disclosure. Outside twelve months, US rights are gone too.
  10. Ask last whether a competitor would practise it. Patentable and worthwhile are different questions, and 58.6% of patents fail the second one.