Britain’s competition authority has fined drugmaker GlaxoSmithKline $54.5 million for stalling the potential entry of generic competitors of an anti-depressant drug Seroxat into the marketplace.

The fine leveled Friday is the largest since the Competition and Markets Authority’s inception in 2014.

The authority fined the pharmaceutical company for making payments and other transfers of more than $75 million to generic suppliers of the drug, also known as paroxetine. The authority says that GSK first sued generic drugmakers Generics (UK) Limited and Alpharma Limited, but later settled, paying for them to delay their entry into the market.

The generic companies were also fined. In all, the authorities leveled 45 million pounds in fines connected to the matter.

GSK (NYSE: GSK) disagrees with the decision and may appeal.

GSK said it disagreed with the ruling and was considering appealing.

“GSK and the generics companies entered into these agreements at the time in order to settle costly, complex and uncertain patent disputes,” a GSK spokesperson said, according to the BBC

“The agreements allowed the generics companies to enter the market early with a paroxetine product and ultimately enabled a saving of over [some $22 million] to the NHS.”

GSK employs several thousand people in the Triangle area.