Looking for new invention ideas for the future usually starts with speculation. It does not have to.

Filing activity is public and countable. Every application is classified, and counting classifications over time shows where inventive effort is actually going.

But rising activity is not straightforwardly good news. It signals commercial interest and it signals crowding, and crowding is what makes claims narrow.

The useful signal is usually adjacent — a specific unsolved problem inside a growing area rather than the area itself.

Read the data yourself

Tool Shows Cost
USPTO Patent Public Search US filings by CPC and date Free
PatentsView Bulk US data, counts and trends Free
Espacenet Worldwide families Free
Google Patents Full text, translations Free
CPC scheme browser What each class covers Free

Classification groups inventions by what they do, not what they are called, which is exactly what a trend question needs.

Counting is the method. Pick a CPC group, count applications per year across five or ten years, and read the direction.

What the counts tell you

Pattern Reading
Rising steadily Sustained commercial interest, increasing crowding
Sharp recent rise New entrants; prior art still thin but closing
Flat and high Mature, well-covered
Falling Interest moving elsewhere — or the problem was solved
Low and flat Quiet — either neglected or uncommercial

Low and flat is ambiguous and worth investigating. Some quiet classes are quiet because nobody needs the technology; others because nobody has looked.

A sharp recent rise is the most actionable pattern, because the field is commercially live but the prior art has not yet accumulated.

The eighteen-month lag

Applications publish at 18 months from earliest priority
What you can count Filed at least 18 months ago
What is invisible Everything filed since
Implication Counts describe the past, not the present

Trend data is retrospective by construction. A class showing rapid growth describes where money was going eighteen months ago, and considerably more has been filed that you cannot see.

Which means you are never early by reading the data. You are informed, which is different.

Crowding cuts both ways

Effect of a crowded field Consequence
Dense prior art Narrower claims
Well-funded incumbents filing Hard to obtain broad coverage
More potential infringers If you get a claim, it matters
More rejections, more rounds Higher prosecution cost
Established vocabulary Easier to search

A narrow patent in a crowded field costs the same as a broad one. Same filing fees, same prosecution, same $14,470 in maintenance fees for a large entity across its life.

And most of them do not survive. Only 41.4% of US utility patents reach full term — see the patent survival curve.

Where an individual can realistically win

Look for Why
A specific unsolved problem inside a growing area Narrow enough that incumbents skipped it
Problems you encounter in your own work Domain knowledge is the real asset
Adjacent applications of a maturing technology Different field, different prior art
Manufacturing and servicing problems Under-filed relative to product features
Cost or simplicity, not capability Incumbents optimise for capability

Domain knowledge beats trend data. Patentable inventions come from understanding a problem well enough to see why existing solutions fall short, and no classification count supplies that.

Trend data tells you where to look. It does not tell you what to build.

Filing is belief, not outcome

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%
Lost at the first fee 14.2%
Lost at the third fee 23.2 points

Computed from 27,273,654 USPTO maintenance fee records covering 8,262,336 US utility patents.

Nearly three in five patents are abandoned by their owners. Filing counts measure how many people believed something was worth protecting; the survival curve measures how often that belief held up.

Read them together. A class with rising filings and high abandonment is a class where a lot of money is being spent on things that did not work out.

Worked example: reading one class

An inventor with maintenance and servicing experience looks at a growing area.

Step Action Finding
1 Count filings in the CPC group, 2016–2024 Rising 3× over the period
2 Identify top assignees 6 large companies, 71% of filings
3 Read 30 recent applications All focused on capability and performance
4 Look for what nobody filed on Field servicing and calibration
5 Count filings on the servicing sub-problem Very few
6 Free prior art search on the specific idea Two close references
7 Read them properly Both require a fixed reference standard
8 Reformulate around self-calibration Novel over both

Why this worked

The growing class was not the opportunity. Six well-funded incumbents were already filing heavily on the obvious problems.

The gap was adjacent. Field servicing is a real cost, and incumbents optimising for capability had not addressed it.

Step seven produced the invention. Reading the close prior art showed what had been tried and where it fell short, which is where the reformulation came from.

Steps one to eight cost nothing except time. See invention ideas.

Novel is not enough

Requirement Test
Novelty (§102) Not disclosed in a single prior art reference
Non-obviousness (§103) Not obvious to a skilled person
Eligibility (§101) Not an abstract idea, natural law or phenomenon
Utility Has a specific, credible use
Enablement (§112) Can be made and used from the description

Non-obviousness fails more applications than novelty. Combining known elements in a predictable way is obvious even when nobody has combined them before.

Eligibility matters most for software and service inventions, where a method of organising human activity is an abstract idea regardless of novelty. See what can be patented.

Search before anything else

Source Why
Google Patents Full text worldwide, translations
USPTO Patent Public Search Classification browsing
Espacenet Foreign families
Product listings and marketplaces A product on sale is prior art
Trade publications Where examiners search least
Academic and conference papers Frequently missed

Search by function in five vocabularies. What you call one thing, the prior art may call another entirely.

Market searching matters as much as database searching. No patent database holds a product that was sold but never patented, and it is prior art all the same.

The search is free and it eliminates most inventions, which makes it the highest- value step in the process.

What trend data cannot do

Cannot Why
Tell you what will be valuable Filing is belief, not outcome
Show current activity 18-month publication lag
Identify unfilled gaps directly Absence is ambiguous
Replace domain knowledge The invention comes from understanding
Predict eligibility outcomes A legal question, not a market one

Absence of filings is ambiguous. A quiet class may be neglected or it may be uncommercial, and the data alone cannot distinguish them.

New invention ideas: the checklist

  1. Count CPC filings over time rather than speculating. The tools are free.
  2. Treat rising activity as crowding as well as opportunity.
  3. Remember the eighteen-month lag. You are seeing the past.
  4. Look for adjacent gaps, not the growing area itself.
  5. Check what the top assignees are optimising for — and what they are not.
  6. Start from a problem you actually understand. Domain knowledge is the asset.
  7. Read filing counts alongside the survival curve. 58.6% are abandoned.
  8. Test for non-obviousness, not just novelty. It fails more applications.
  9. Search products as well as patents. Anything on sale is prior art.
  10. Read the close references properly. The reformulation is usually in them.