The High Court dealt Allergan a massive blow last week when it revoked the patent for Botox, and now the pharmaceutical company is facing a worldwide battle to hold on to the trademark for the drug.

The judgment, one of Mr Justice Kitchin’s first, is a blow to Allergan, which owns a patent portfolio for Botox, which is under attack in a number of jurisdictions.

“The judgment reveals a naked commercial attempt by Allergan to prolong and expand its monopoly rights over Botox,” said one patents specialist who did not work on the case. Allergan’s attention will now turn to defending its trademarks. Rival pharma Basic Research/Klein-Becker has ditched DLA Piper and turned to Nabarro Nathanson to coordinate the multinational trademark dispute aimed at revoking the Botox trademark.

A UK trial is due in January, which Nabarros partners Jonathan Radcliffe and Guy Heath are coordinating with lawyers in the US, Brazil, France and the Netherlands. They have instructed Geoffrey Hobbs QC of One Essex Court.

Allergan used Bird & Bird head of IP Morag Macdonald on the patent dispute, with Simon Thorley of 3 New Square and Piers Acland of 11 South Square. It has turned to Taylor Wessing head of IP Charles Lloyd for the trademark fight.

The London IP practice of Jones Day won its first big patent case in the High Court with its victory for Merz Pharma, which invalidated Allergan’s UK patent for Botox.

Partner Alastair McCulloch and senior associate Neil Coulsen, who also worked on the case, joined Jones Day from Bristows last April to relaunch the firm’s IP team as a hard IP practice following the departure of former head of IP Charters Macdonald-Brown and partner Simon Chalkley, who launched an independent boutique named Redd.

Jones Day instructed Anthony Watson of 3 New Square and Andrew Lykiardopoulos of 8 New Square, who also used to practise at Bristows.