This dataset identifies 1,924 patent families published or filed between 2015 and mid-2026 that reference radioligand therapy, radioimmunoconjugates or chelator conjugation alongside a practical constraint such as isotope availability, chelate stability, specific activity or dosimetry. This is a defined search scope, not a count of every patent touching radiochemistry broadly, so the true universe of related filings is larger. Because publication lags filing by roughly 18 months, the most recent one to two years in the total will keep rising as more records publish.

The ranked leader in this dataset holds 146 records, with a fairly steep drop to 88 at fifth place and 45 at tenth — indicating a distinct top tier rather than a flat field. The top 5 assignees together account for 28.7% of all 1,924 records, and the top 10 account for 41.2%. Beyond that group the ranking spreads across a long tail of companies and institutions each holding a handful of families, including specialist radioligand developers, large pharmaceutical companies, and academic medical centres.

Yes, based on the last fully complete years of data: filings grew from 96 in 2021 to 181 in 2024, an 89% increase. The single highest filing year on record so far is 2018 at 201. Figures for 2025 and 2026 appear lower only because publication typically lags actual filing by around 18 months, not because activity has slowed — those years should not yet be read as a decline.

A61K, medicinal preparations, appears on 87.2% of the 1,924 records and is by far the most crowded classification, followed by A61P (therapeutic activity, 49.5%) and C07K (peptides and proteins, 40.5%). Less crowded areas include G01N (material analysis and testing, 16.8%), C07D (heterocyclic compounds, 8.4%), C12N (microorganisms and genetic engineering, 8.2%), C07B (organic chemistry methods, 5.9%) and C12P (fermentation and enzymatic synthesis, 4.8%). Because a single record can carry multiple classes, these are shares of all records rather than mutually exclusive slices, and the lower-share classes are where analytical and process claims tend to face less crowded prior art.

US20170112951A1 describes a one-step method for chelating actinium-225 to an antibody or monoclonal antibody construct through a bifunctional ligand in a 3-arm configuration, performed at physiological temperature around 37 degrees Celsius. It claims methods for increasing radiochemical yield and for producing high specific activity actinium-225 complexes, along with the complexes and pharmaceutical compositions themselves. For anyone developing an actinium-225 or similarly alpha-emitting radioconjugate, this filing is relevant prior art specifically around one-step, physiological-temperature chelation methods aimed at high specific activity, and any competing method should be checked against its specific process claims rather than assumed distinct on target biology alone.