Merck KGaA has reasserted its rights to the Merck name after a three-year court-room tussle with Merck & Co of the US.
Under a 1955 agreement Germany's Merck is allow to use the name in all countries with the exception of the US and Canada, while Merck & Co's operations outside North America go under the name MSD, or Merck Sharp & Dohme.
Merck launched proceedings three years ago in the English courts against its US rival, claiming Merck & Co had breached their decades-old deal over use of the name.
The court has now sides with Germany's Merck, finding that MSD breached the agreement by using 'Merck' alone in the UK either as a trade mark or a name, online or offline.
Friederike Rotsch, general counsel at Merck, said: "Our objective has been to protect the status quo established in the existing agreement.
“Therefore, we are pleased that the English court has upheld our argument that MSD's use of our name and brand 'Merck' in our territories is beyond the limits agreed with MSD."
The court-room decision found Merck was entitled to an order preventing MSD from describing itself in any printed or digital material addressed to the UK as 'Merck' alone, and restraining MSD's use of the trade mark 'Merck' alone.
The judge also held that MSD's use of 'Merck' as part of the branding on its global websites were directed to the UK and therefore infringed Merck's trade mark rights in the UK.
The decision comes some three months after Merck launched an eye-catching new brand that saw its Merck Serono and Merck Millipore divisions now known simply as Merck in all markets outside the US and Canada. (For more on the two companies' backstory see A tale of two Mercks.)