Sungrow USA Seeks Declaratory Judgment Against Gridscale on Seven Inverter Patents Asserted Against Its BESS Products.

Sungrow USA Corporation v. Gridscale Solutions, LLC, No. 8:26-cv-03230 (C.D. Cal.), is a 35-page complaint for declaratory judgment filed November 2, 2026, ECF No. 1, with a jury demand. Sungrow USA is a Delaware corporation based in Costa Mesa, California. The complaint alleges, on information and belief, that Gridscale is a Texas limited liability company based in Plano, Texas.

Why Sungrow filed

Sungrow alleges an actual controversy under the Declaratory Judgment Act, 28 U.S.C. §§ 2201 and 2202, based on Gridscale's infringement assertions and licensing demands to Sungrow, its subsidiaries and affiliates, and its customers. It alleges, on information and belief, that Gridscale is a non-practicing entity that acquired the patents in suit in May 2026 as part of a 50-patent portfolio from another company. It says Gridscale sued a Sungrow customer in the Eastern District of Virginia, Nos. 1:26-cv-01403-MSN-WEF and 1:26-cv-03030-MSN-WEF, on the '642, '884, and '454 patents, and that the customer sent Sungrow a September 25, 2026 indemnification notice about Sungrow products it uses in battery energy storage systems.

The complaint says Gridscale wrote to Sungrow directly on September 22, 2026, accusing Sungrow's PowerTitan battery energy storage products, power conversion systems, controllers, and communication products, and that two other Sungrow customers received Gridscale demands, one of which asked Sungrow to take up its defense. Sungrow alleges that the patents in suit are directed to single-phase power conversion, while its products use three-phase technology.

The patents in suit

The complaint identifies the patents in suit as U.S. Patents 8,796,884 (Energy conversion systems with power control), 8,842,454 (Inverter array with localized inverter control), 9,225,256 (Apparatus and method for controlling DC-AC power conversion), 8,279,642 (Apparatus for converting direct current to alternating current using an active filter to reduce double-frequency ripple power of bus waveform), 10,516,270 (Method and apparatus for coordination of generators in droop controlled microgrids using hysteresis), 11,641,110 (Apparatus and method for reactive power control), and 9,160,408 (System and method for establishing communication with an array of inverters), and attaches copies as Exhibits A through G.

Counts and relief

The complaint pleads fourteen counts: for each of the seven patents, a count seeking a declaration of noninfringement and a count seeking a declaration of invalidity (Counts One through Fourteen). The prayer asks for declarations that Sungrow has not infringed and is not infringing any valid claims of the patents in suit; that the asserted claims of those patents are invalid or otherwise unpatentable or ineligible; a permanent injunction barring assertion of the patents against Sungrow or any third party based on alleged use of Sungrow's accused products; judgment for Sungrow; a finding that the case is exceptional under 35 U.S.C. § 285; costs, expenses, and attorneys' fees; and other relief.

Docket activity

On the filing day Sungrow filed a civil cover sheet, a report on the filing of an action regarding a patent or trademark, a corporate disclosure statement, and a request for the clerk to issue summons.

What to watch next

Watch for issuance and service of the summons and for Gridscale's answer or motion to dismiss.