What real prosecution shows
Three measurements against public USPTO records: how well it reads an Office Action, what real continuations changed from their parents, and where it looks when it proposes what a continuation could claim. Every application is named, so you can check any row.
Small studies: 2 file histories, 20 families and 11 scored, all of them public.
1. Reading an Office Action
On two real file histories, a 9-billion-parameter model on a laptop found every rejection, and no model named a reference the paper does not contain.
The app reads a Patent Center "download all documents" file, scanned pages included, and reports each rejection an Office Action states and the reasons a Notice of Allowance gives, with the quotation each came from. We scored that reading against the record, read by hand, on the file histories of 18/541,216 and 19/180,870: their Office Actions and their Notice of Allowance. One rejection is one of the examiner's own headings: a ground, the claims it covers and the references it applies, as the Office Action groups them.
| Model | Run | Rejections found | References found | References named that the paper does not contain | Other citations listed as references | Examiner's stated reasons found |
|---|---|---|---|---|---|---|
Claude Sonnet 5.5 | remote | 10 of 10 | 13 of 13 | 0 | 0 | 2 of 2 |
kimi-k2.5 | remote | 10 of 10 | 13 of 13 | 0 | 0 | 2 of 2 |
qwen3.5:9b | on a laptop | 10 of 10 | 12 of 13 | 0 | 0 | 2 of 2 |
qwen3.5:9b | through OpenRouter | 9 of 10 | 13 of 13 | 0 | 3 | did not finish |
The model that found every rejection ran on a laptop, the configuration that keeps a file on the machine. The same model reached through OpenRouter did worse on this run and some of its calls ran to the time limit: a result for that route rather than for the model, since OpenRouter chooses the host and hosts differ in how they serve it.
No model named a reference the paper does not contain, so the app's own check, which
withholds any reference it cannot find in the paper, had nothing to withhold.
The qwen3.5:9b run through OpenRouter listed 3 citations that are not
references of record, a statute and a court decision among them; they are in the paper, so
that check passed them, and the app now withholds statutes and case law as a separate step,
a change made because of this run.
Scored against the record as read by hand; a patent practitioner is checking that reading, and this table will change if it does. One entry is open: the Final Rejection in the second file states its obviousness rejection over two references, then applies a third to later claims, and the hand reading lists all three. Read as two, the local model's one missed reference disappears; the rejection counts are the same either way. The last column counts the reasons a Notice of Allowance states, where it states them; the reasons for allowance are not always written out.
2. What real continuations changed
Limitations added during prosecution were left out of the continuation about 2.5 times as often as limitations filed with the application.
The app marks every limitation of a parent's allowed claims as filed with the application or added in a round of prosecution. We asked whether that distinction lines up with what practitioners actually did in the continuations that followed. 20 families, sampled from the USPTO's public data: each a parent allowed after at least two Office Actions over prior art, and a continuation filed from it. For every limitation of the parent's allowed independent claims, we checked whether the continuation's independent claims still carry it.
Drawn at random (seed 20260929) from continuations filed between 2022-01-01 and 2023-12-31 that issued as patents, no more than three from any one technology group; 122 candidates were examined to keep 20, and a family was kept only if its parent had at least two Office Actions over prior art and both claim sets could be read from the USPTO's text. That selects heavily prosecuted parents on purpose, so this describes those families, not continuations in general.
| Limitation in the parent's allowed claims | Left out of the continuation's independent claims (most of its wording gone) |
|---|---|
| Filed with the application | 25 of 197 (13%) |
| Added during prosecution | 35 of 111 (32%) |
| All of them | 60 of 308 (19%) |
Limitations added during prosecution were left out about 2.5 times as often as filed ones: a difference of 19 points, with a 95% interval of 2 to 35 points when whole families are resampled. It holds when any one family is removed.
When each continuation was filed matters, because one filed before its parent's claims were final may have been drafted before a limitation existed. 17 of the 20 were filed after the parent was allowed. Over those alone the figures are 6% against 23% (22 of 94 added limitations), a difference of 17 points with an interval of 4 to 31.
It is a pattern across the sample, not a rule each family follows. Of the 15 families with both kinds of limitation, the continuation left out added limitations more often in 8, less often in 4, and equally often in 3. Each family is listed below.
This describes what practitioners did in 20 families; it is not a recommendation. It says nothing about why each continuation took the shape it did, and some pursued a different embodiment altogether. What it supports is that knowing when each limitation entered the claims is worth having in front of you, which is why the app shows it.
"Left out" is a test of wording, not of substance: fewer than half of the limitation's significant words appear in the continuation's independent claims. A limitation reworded, split across several, or recast in another kind of claim can count as left out while its substance remains; a practitioner's reading of each row is what would settle it. A stricter test, the exact phrase or nine tenths of its words, gives 46% against 82%: the same direction, larger, and inflated by rewording. The earlier-versus-later distinction within prosecution did not hold in this sample and is not claimed.
Every family
Every family by application number, so any row can be looked up in Patent Center.
| Parent | Parent allowed | Continuation | Continuation filed | Art unit | Filed, left out | Added, left out |
|---|---|---|---|---|---|---|
| 14/893,689 | 2022-01-20 | 17/681,899 | 2022-02-28 | 1798 | 0 of 0 | 2 of 7 |
| 16/085,793 | 2022-08-31 | 18/070,557 | 2022-11-29 | 3752 | 0 of 3 | 0 of 7 |
| 16/485,486 | 2022-10-13 | 18/157,310 | 2023-01-20 | 2686 | 2 of 21 | 0 of 4 |
| 16/525,438 | 2021-10-21 | 17/677,136 | 2022-02-22 | 2613 | 2 of 7 | 2 of 5 |
| 16/589,636 | 2023-07-05 | 18/239,553 | 2023-08-29 | 2666 | 0 of 7 | 2 of 15 |
| 16/615,974 | 2022-10-26 | 18/174,702 | 2023-02-27 | 3676 | 2 of 7 | 1 of 10 |
| 16/645,022 | 2023-06-27 | 18/465,810 | 2023-09-12 | 3746 | 2 of 3 | 0 of 1 |
| 16/820,519 | 2023-03-14 | 18/065,160 | 2022-12-13 (before allowance) | 2497 | 3 of 8 | 3 of 5 |
| 16/853,828 | 2022-10-06 | 18/075,487 | 2022-12-06 | 2812 | 0 of 8 | 0 of 0 |
| 16/858,891 | 2022-09-23 | 18/157,395 | 2023-01-20 | 2812 | 0 of 10 | 3 of 5 |
| 16/885,445 | 2022-01-06 | 17/709,763 | 2022-03-31 | 2433 | 0 of 12 | 6 of 18 |
| 16/941,358 | 2021-12-16 | 17/735,992 | 2022-05-03 | 3711 | 2 of 34 | 0 of 2 |
| 16/951,296 | 2023-06-07 | 18/465,924 | 2023-09-12 | 2634 | 0 of 9 | 1 of 3 |
| 17/055,713 | 2022-08-01 | 17/985,859 | 2022-11-13 | 2478 | 1 of 17 | 0 of 0 |
| 17/095,189 | 2022-10-18 | 18/065,161 | 2022-12-13 | 3672 | 0 of 16 | 0 of 6 |
| 17/130,243 | 2022-12-12 | 18/297,671 | 2023-04-10 | 2139 | 0 of 10 | 5 of 7 |
| 17/167,459 | 2022-03-30 | 17/709,680 | 2022-03-31 | 3677 | 0 of 1 | 0 of 4 |
| 17/232,598 | 2023-02-09 | 17/985,743 | 2022-11-11 (before allowance) | 2818 | 8 of 9 | 0 of 0 |
| 17/536,510 | 2022-11-08 | 18/093,647 | 2023-01-05 | 3632 | 0 of 7 | 0 of 0 |
| 18/132,074 | 2024-08-14 | 18/132,064 | 2023-04-07 (before allowance) | 2637 | 3 of 8 | 10 of 12 |
3. Where the app looks, and what it changed
The app reads the specification for potential subject matter beyond the parent's claims, as candidates for the practitioner, each tied to a passage of the specification; in the app that is the Embodiments step, and this measures the pass it builds on. We checked whether those passages sit near where each real continuation's new claim elements came from, and compared the app with two baselines at the same number of positions: random places in the specification, and the places the parent's own claims came from.
| Model | Run | Proposals near what the continuation claimed | Random places | Where the parent's claims came from | All three, within about 3 paragraphs |
|---|---|---|---|---|---|
Claude Sonnet 5.5 | remote | 16% (5 of 47) | 38% | 68% | 63%, 71%, 77% |
kimi-k2.5 | remote | 13% (3 of 47) | 35% | 67% | 51%, 67%, 76% |
qwen3.5:9b | on this machine | 45% (19 of 47) | 36% | 67% | 68%, 69%, 76% |
This one is a finding against the app. Its first step looks for matter the parent left unclaimed, and the stronger models do that most faithfully, which put them below the random baseline on most families. The continuations mostly stayed on the parent's own ground: 6 of the 17 we could read added nothing to the parent's claims at all, only leaving limitations out. That is the reason the first step is being revisited, and the reason the record of section 2 matters.
11 families could be scored: the rest had no machine-readable specification on the USPTO's system or added no new element. A new element is a limitation of the continuation's independent claims, of at least three significant words, that no allowed claim of the parent carries in its wording (the exact phrase or nine tenths of its words). The percentages are averaged family by family; the counts in brackets pool every new element across those families, which is why the two can differ. "Near" is within about a paragraph of where the element's words sit in the specification; the last column repeats all three at about 3 paragraphs, where the gaps narrow and the parent's own ground still leads in every row. Each baseline uses the same number of positions as the app located: random places are drawn uniformly across the specification, and the parent's positions are sampled from where its own claims came from, each averaged over 200 draws from a fixed seed.
What these measurements cover
How it reads a file, what practitioners did, and where it looks. They do not judge whether any continuation was well drafted or what any application should claim, and the app does not assess patentability. The drafting benchmark, a separate study, is on the benchmark page, and one complete drafting run is printed on the sample page.
For a far larger study of when and why continuing applications are filed, covering patents granted from 1981 to 2020, see Righi, Cannito and Vladasel (Research Policy, 2023).
The measurements on this page are published under CC BY 4.0: reuse them with credit to Obviously Not, Inc. The records they are drawn from are public USPTO data.