San Francisco, Aug 21 : A federal judge has upheld an earlier ruling from the US Patent and Trademark Office that a piece of art created by artificial intelligence (AI) cannot be copyrighted. US District Judge Beryl Howell said that the copyright law has "never stretched so far" to "protect works generated by new forms of technology operating absent any guiding human hand," reports Hollywood Reporter. The ruling came in an order turning down computer scientist Stephen Thaler's bid challenging the government's position refusing to register works made by AI. The US Copyright Office had refused a copyright to Thaler for an AI-generated image made with the Creativity Machine algorithm he had created. Thaler tried multiple times to copyright the image "as a work-for-hire to the owner of the Creativity Machine". Thaler also sued the US Copyright Office, claiming its denial was "arbitrary, capricious and not in accordance with the law." However, Howell ruled that "human authorship is a bedrock requirement of copyright." Thaler now plans to appeal the case, according to the report. In April this year, the US Supreme Court also declined to hear a challenge by Thaler to the US Patent and Trademark Office's refusal to issue patents for the work his AI system created. In 2018, the Ninth Circuit Court of Appeals in the US threw out a copyright lawsuit brought by a selfie-taking monkey. /IANS