The most-cited record in this dataset is a 1990s-era US patent on a low-density, high-strength Al-Li alloy, which remains the most-referenced foundational filing. Behind it sit a small cluster of aerospace-linked assignees whose filings date largely from the 1980s and 1990s, alongside a 2010s entrant focused on lower-cost, high-formability compositions. No single company dominates the field today; the historically strongest assignees show no filings in the most recent tracked year, so current activity is genuinely dispersed.

Filing volume in this niche never exceeded four families in a single year, and by the 2022 midpoint had dropped to roughly one a year. That pattern is consistent with a mature, low-volume specialist field rather than a collapsing one — durability and fatigue claims for this alloy family were largely staked out earlier, leaving fewer white-space compositions to claim. It is also worth treating the final one to two years of any trend chart with caution, since publication typically lags actual filing by around eighteen months.

C22C, covering alloy compositions, accounts for the large majority of records in this search, followed by C22F, non-ferrous metal heat treatment. Casting (B22D) appears in a handful of filings, while rolling, extrusion, sheet-metal forming and powder metallurgy each show up only once or twice. Anyone drafting new claims should expect dense prior art in composition and heat-treatment language, and comparatively open ground in the processing-route classes.