The dataset's assignee ranking covers 100 companies drawn from 4,229 records, with the leading assignee holding 130 records and the fifth-ranked holding 61. The combined top 5 account for 10.5% of all records in scope, which is a modest share for a field leader — ownership is spread across pharmaceutical majors, a consumer-products company and university-affiliated filers rather than concentrated in one hand. This means freedom-to-operate analysis needs to check several portfolios individually rather than relying on a single dominant player's claims.

Filing rose from 264 records in 2017 to a peak of 295 in 2021, then fell to 121 by 2024 — a decline of 59% over that three-year span, using only complete filing years. Publication lags filing by roughly 18 months, so the lower counts shown for 2025 and 2026 in raw data are not yet reliable evidence of a continuing trend. Based on the complete-year data, the field has genuinely cooled since its 2021 peak, but it has not disappeared — 121 records in 2024 is still a substantial base.

A61K, medicinal preparations, appears on 91.7% of the 4,229 records in scope, making it by far the dominant classification. A61P, covering therapeutic activity of compounds, follows at 43.5%, while A61Q cosmetics-use classification trails at 14.0%. Because a single record can carry multiple IPC codes, these percentages overlap and sum to more than 100% — they describe how claim language is framed, not mutually exclusive categories of invention.

The lower-density IPC classes in this corpus — A61Q cosmetics-use at 14.0%, C07D heterocyclic compounds at 4.7%, and C07K peptides and proteins at 3.3% — carry comparatively less claim density than the dominant A61K medicinal-preparations class at 91.7%. That gap suggests cosmetic-only skin-feel claims and peptide-carrier semisolid vehicles are less crowded than therapeutic formulation claims generally. High density in A61K signals occupied claim space, not necessarily a mature or exhausted technology, so a narrowly drafted claim there can still succeed.

US5698589A covers a water-based topical cream combining nitroglycerin, a penetration enhancer, water, a thickener and an emulsifier, along with methods of preparation and specific therapeutic uses including erectile dysfunction and microvascular disease treatment. Its claims are tied to that specific active-ingredient and vehicle combination rather than to penetration enhancers or emulsifier systems generally, so it does not block semisolid formulations built around other actives. Anyone formulating nitroglycerin-based topical creams with a similar penetration-enhancer and emulsifier-thickener structure should review its claim scope closely; formulations using different actives or vehicle chemistries sit outside its direct reach.