According to Foresight News, Ethereum Name Service (ENS) has submitted an application to the United States Patent and Trademark Office, questioning the validity of the patent obtained by Unstoppable Domains on open-source technology developed by ENS Labs. ENS has accused Unstoppable Domains of theft for patenting the ENS technology and has criticized them for refusing to open-source the patent or make any irrevocable commitments. This move by ENS is seen as a significant step in the ongoing dispute between the two entities over the ownership and use of the open-source technology.