The assignee ranking is led by one company holding 1,753 of the 15,742 records in scope, well ahead of the fifth-ranked assignee at 585. The top five assignees combined account for 35.1% of all records, and the top ten reach 46.5%, so filing activity is concentrated among a small group of legacy petrochemical and catalyst companies rather than spread evenly across the field. Anyone evaluating freedom to operate should start with these leaders’ portfolios before looking at the long tail of single-filing entrants.

Filings peaked in 2017 at 572 records and declined to 226 by 2024, a 26% drop across that span using the most recent years with reliable, largely-published data. Figures for 2025 and 2026 appear lower still, but that reflects publication lag of roughly 18 months rather than an actual collapse in filing. The honest read is that the field has cooled from its 2017 peak, not that it has stopped.

Both routes start from methanol over a zeolite catalyst, but MTO claims target ethylene and propylene yield and typically hinge on reactor conditions like fluidized-bed heat removal and the propylene-to-ethylene ratio, while MTG claims target gasoline-range hydrocarbons and lean more on catalyst shape-selectivity and pore geometry. This dataset captures both routes because the underlying reactor-engineering and catalyst-regeneration problems overlap heavily between them. A given company’s portfolio often spans both if it operates across fuel and chemical product lines.