LONDON (Reuters) - Apple Inc (AAPL.O) infringed two telecommunications patents used in devices including iPhones and iPads, London's Court of Appeal ruled on Tuesday, dismissing the tech giant's appeal in a long-running dispute with a U.S. patent holder.

Texas-based Optis Cellular Technology LLC sued Apple in 2019 over its use of patents which Optis says are essential to certain technological standards, such as 4G.

London's High Court ruled last year that two of Optis' 4G patents were so-called standard essential patents and that Apple had infringed them.

Apple appealed against that decision in May, arguing that the two patents in issue were not essential to 4G standards and that it had not infringed the patents.

But its challenge was rejected by the Court of Appeal, with Judge Colin Birss saying in a written ruling that the High Court was "right to reject (Apple's) argument for non-infringement" and on the issue of the patents being essential.

Apple and Optis did not immediately respond to a request for comment.

Tuesday's ruling is the latest decision in the legal battle between Apple and Optis, which began in 2019 and has prompted six separate trials and several appellate hearings in Britain alone.

The Court of Appeal last month upheld an appeal by Optis against an earlier decision to revoke two other 4G-related patents, following a ruling in October that Optis is entitled to an injunction to stop Apple infringing its patents before a court has ruled on the fair, reasonable and non-discriminatory terms of use.

Apple was granted permission earlier this year to appeal against the October ruling.