Within this 68-record dataset, one assignee holds a clearly leading position with 28 records, well ahead of the rest of the ranked list where fifth place sits at only 6. That gap suggests the leader has built defensive depth around core column and process-control claims over many years. Any freedom-to-operate check in this space should start with that filer’s portfolio before looking at the thinner mid-tier.

A deethanizer is a distillation column that removes ethane from a mixed NGL stream ahead of further fractionation into propane, butanes and heavier products. It attracts filings because small changes to reflux ratio, tray design or reboiler operation directly affect product purity and energy cost at commercial scale, and those operating parameters are exactly what this dataset’s search terms target. Most of the corpus classifies under refining (C10G) or compound chemistry (C07C) rather than under separation-equipment classes, showing the process conditions are claimed as often as the hardware.

Filings in this dataset started from zero in 2017 and built up to a peak of 25 records in 2023, the highest single year in the covered period. The most recent years, including 2026, show very few records, but that is expected: publication typically lags filing by around 18 months, so recent activity is always undercounted at the time a search is run. A reliable growth rate cannot be calculated from this set because fewer than four complete years remain once that lag is accounted for.