No — filing peaked in 2021 at 190 records and has declined in the years since, including a 2022 midpoint of 157. The 2026 figure looks even lower but is a partial year because publication typically lags filing by around 18 months, so the true recent trend is somewhat higher than the raw chart shows. Overall, the shape is flat-to-declining rather than growing, which suggests the core claim space is largely occupied rather than expanding.

China’s receiving office carries 1,432 of the 1,602 tracked filings, far more than the United States (51), Europe or Japan (20 each) or WIPO (12). That imbalance means the prior-art wall is much thinner outside China, though a low count there can also reflect fewer local competitors rather than open claim space — a separate FTO search in each target jurisdiction is still necessary.

US20190309773A1, assigned to Caterpillar Global Mining LLC and published 2019-10-10, is the representative record in this dataset for seal-life improvement. It describes a head end seal assembly using a main seal groove paired with an adjacent thermoplastic coating-ring groove, where the coating ring deposits polymer into rod-surface indentations to extend service life. It sits within the F16J seal/gasket class, one of the less densely claimed subclasses relative to F15B actuator hardware.