Alphabet Inc (NASDAQ:GOOG)-owned Google is facing a billion-pound court battle over claims it abused its power in the online advertising market after a competition tribunal ruled there is a case to answer.
Ad Tech Collective Action was given the go-ahead to proceed with a £13.6 billion ($17.2 billion) writ, which alleges the Alphabet subsidiary's actions in search engine advertising penalised online publishers.
“This is a decision of major importance to the victims of Google’s anti-competitive conduct in ad tech," said former Ofcom director Claudio Pollack, a partner in Ad Tech Collective Action.
"Google will now have to answer for its practices in a full trial."
Oliver Bethell, Google's legal director, described the lawsuit as "speculative and opportunistic".
"We’ll oppose it vigorously and on the facts," he added.
Ad Tech Collective Action said Google promoted its products and services more prominently than rivals, resulting in them having to pay hefty fees to get responses to advertising.
As an opt-out case, all relevant UK publishers are included unless they indicate otherwise.
Google is already under investigation by regulators in the UK, Europe, and the US into its ad tech business and has already received substantial fines from the EU over anti-competitive behaviour.