Fan-Out Wafer Level Packaging (FOWLP) reconstitutes a die into a molding compound before applying redistribution layers, allowing I/O connections to be routed ('fanned out') beyond the physical edge of the die rather than staying within it, as standard fan-in WLP requires. This gives more room for I/O pads and package balls on the same die size, which is why it is common in RF front-end and application-processor packaging. The patent record in this dataset reflects that structural distinction: claims cluster around molding compound formulation, redistribution layer formation and die-shift control, all of which are specific to the fan-out reconstitution step rather than the die itself.

The recent-year momentum data in this dataset shows a mix of large integrated device manufacturers, foundries and OSAT (outsourced assembly and test) providers among the historically active filers, several of which show reduced or zero filing activity in the latest tracked year. Because publication lags real filing dates by roughly 18 months, current-year rankings should be treated as provisional. The most reliable read on who is actively defending claim territory right now is the combination of overall family count and recent filing trend, not citation count alone, since citation counts favour older foundational filings.

Filing volume in this dataset peaked in 2017 at 107 families and has trended down through a 2022 midpoint of 60, without recovering. This pattern is consistent with a technology whose foundational structural claims — basic die encapsulation, RDL formation, package ball layout — were staked out early, leaving later filers to compete for narrower process and materials claims rather than broad structural ones. It does not necessarily indicate declining commercial adoption of FOWLP itself, only that the rate of new patent claims in this specific claim space has slowed.

The IPC composition data shows heavy concentration in H01L and H10W, with much smaller record counts in H01Q (antenna integration), H10D, H10N, H05K and H10B. These smaller subclasses — particularly antenna-in-package integration and memory-embedded fan-out — carry noticeably fewer filings than the core structural claim space, suggesting room for narrower claims that combine FOWLP process steps with those adjacent functions. Any filing strategy targeting this white space should still be checked against the highest-cited foundational patents, since some structural elements may still be covered even in a lower-density subclass.

The United States receives the largest share of filings in this dataset at 556 records, followed by China at 86 and Taiwan at 81, with the EPO, South Korea and the WIPO/PCT route each receiving smaller numbers. This distribution tracks where major packaging foundries, OSATs and fabless design houses operate and file first. A company assessing freedom-to-operate risk should prioritise US and Taiwan filings given their volume, without ignoring the smaller but still meaningful China filing base.