2023 is when grid-forming stopped being a concept and became a patent category. The filing data shows the field shifting from broad capability claims to specific control-method claims — the signature of a maturing technology where the easy ground is taken and the fights move to the details.
General Electric is the clearest named anchor. Within the year GE took both US11680558B2 (grid-forming via virtual impedance) and US11843252B2 (sub-synchronous damping) — two distinct, narrow control-method grants. That is a deliberate pattern: not one big claim, but several specific ones fencing different pieces of the grid-forming control problem.
Alongside GE sit inverter specialists (SolarEdge appears in the facet) and, notably, a cluster of independent-inventor publications — Haroon Inam's US20230109775A1 (grid-forming over a distribution grid) and US20230216301A1 (power-flow control with grid-forming capability) stake foundational distribution-level claims from a single inventor.
The strategic read: when a field moves from one or two big players to a mix of incumbents filing narrow method claims plus independent inventors filing broad concept claims, it is consolidating fast. The incumbents are racing to fence the specific techniques (damping, impedance) while the broad-concept ground is being claimed by whoever filed earliest.
The usual landscape caveat: one year, one CPC cluster, publications and grants mixed. But the coming-of-age pattern is robust and consistent with the deployment timeline — grid-forming moved from research to requirement as renewable penetration crossed thresholds, and the 2023 IP surge tracks that transition. Watch the citation trail from GE's narrow grants; whoever cites them is building in the same neighborhood.