This landscape tracks 165 published patent records filed between 2015 and the 2026 data cut-off, covering isolation methods, cargo loading, biodistribution tracking, scalable production and potency definition. That figure counts patent families in the assignee ranking, which is the fairer unit than raw document counts because it neutralizes multi-jurisdiction and continuation filings. Filing activity peaked in 2021 at 32 records and had fallen to 17 by 2024, the last year that can be treated as complete given typical publication lag.

The top assignee in this dataset holds 17 of the 165 records in scope, with a cluster of academic and biotherapeutics-focused filers close behind — fifth place holds 7 records and tenth place holds 6. Together the five leading assignees account for 37.0% of all records, and the top ten account for 57.6%. Beyond that, the ranking includes 58 companies total, most holding only one or two records, so the field is concentrated at the top but has a substantial long tail of smaller programs.

Relative to the field’s core, yes: separation-process claims under IPC class B01D appear on only 8.5% of the 165 records, far below the 70.9% carrying medicinal-preparation claims and 62.4% carrying genetic-engineering claims. That gap is notable because scalable, reproducible isolation is a named bottleneck for clinical translation, and the claim density there has not caught up with the formulation side of the field. New filers should still run a specific claim against the corpus before assuming open ground, since 165 records is enough to create pockets of dense prior art even in a comparatively thin class.