Doubled haploid breeding produces fully homozygous plant lines in one or two generations instead of the five to eight generations needed for conventional inbreeding, by inducing haploid embryos and then doubling their chromosome number with an agent such as colchicine. It matters for patent strategy because the technique touches two separable inventive steps — haploid induction and chromosome doubling — and filers have historically claimed each separately, which is why the patent record splits cleanly across A01H plant-breeding claims and C12N genetic-engineering claims. Anyone developing a new inducer line or doubling protocol needs to clear both categories, not just one.

The assignee ranking covers 94 companies, and it is heavily front-loaded: the top five together hold 213 of the 403 records in scope, or 52.9% of the field, with the single leading assignee alone accounting for 63 records. That is a much steeper drop than a typical even distribution — the fifth-ranked assignee sits at only 30 records and the tenth at 12. Practically, this means a small number of portfolios cover the majority of core claim territory, and those are the ones worth screening first in any competitive or freedom-to-operate analysis.

Not on this dataset's trend. Filing peaked at 39 records in 2017 and had fallen to 30 by the 2022 midpoint, a flat-to-declining pattern rather than sustained growth, and the most recent tracked year shows only 1 record. Because publication typically lags filing by around 18 months, the last one to two years understate real activity, but the multi-year trend before that lag window still points downward from the 2017 high rather than upward.

US20100169999A1, assigned to Corteva Agriscience, discloses methods for inducing chromosome doubling in plants using chromosome-doubling agents selected for low mammalian toxicity, claiming improved mortality and doubling-rate outcomes over prior agents. It is cited 30 times within this corpus, making it one of the more referenced doubling-agent disclosures in the field. Whether it blocks a specific new project depends on the exact agent, dosage and species used — a narrow reading around agent chemistry and toxicity profile is where a design-around is most likely to be viable, but that requires reading the full claim set rather than the abstract alone.

The IPC composition data shows claim density concentrated in A01H (96.3% of 403 records) and C12N (53.1%), while G01N material analysis and testing appears on only 1.5% of records and A01N, A01C and A01G are each below 1.5% as well. That leaves detection instrumentation, field-scale phenotyping of haploid versus diploid seedlings, and combined gene-editing-plus-induction constructs comparatively under-claimed relative to the core induction and doubling chemistry. These thinner classes are a reasonable starting point for a first claim that avoids the densest prior art.