T1 Energy has acquired foundational TOPCon (Tunnel Oxide Passivated Contact) solar cell and module patents, along with related intellectual property assets from Singapore-based Evervolt Green Energy Holding for US$135 million. The acquisition gives T1 full ownership of technology it previously licensed and eliminates future royalty obligations associated with that portfolio.

According to T1 Energy, the patents relate to TOPCon solar cells and modules and support the company’s strategy to build an integrated U.S. silicon-based solar manufacturing supply chain. The transaction shifts T1 from a technology licensee to an owner of the underlying intellectual property.

The acquisition comes as intellectual property issues become increasingly prominent in the solar industry. First Solar, which acquired TOPCon-related patents through its purchase of TetraSun in 2013, has pursued patent infringement litigation involving TOPCon manufacturing methods and sought to enforce its patent portfolio in multiple jurisdictions.

In January 2026, the U.S. Patent and Trademark Office (USPTO) denied review requests seeking to invalidate two First Solar patents, U.S. patents 9,130,074 and 9,666,732. The patents remained in force following the USPTO's decision while related litigation continued.

Public reports describing the T1-Evervolt transaction characterize the acquired assets as foundational TOPCon patents and intellectual property but do not identify the specific patent numbers included in the portfolio.

- Cathy Li