Seems that Wikipedia is confused. Sensodyne was originally an American product, but it was later purchased by GSK, which is a British company, which then split, and Sensodyne is now owned by Haleon, a British company.

History

Sensodyne is a brand of toothpaste that was first sold by Block Drug, a Brooklyn, New York-based company established in 1907 by pharmacist Alexander Block.[1]

In 2000, Block Drug was purchased by Smith Kline Beecham P.L.C.,[11] which became GlaxoSmithKline (NYSE:GSK).[12]

Sensodyne became a part of Haleon, a British multinational consumer healthcare corporation, in July 2022, following the establishment of Haleon as a separate entity through a corporate spin-off from GSK.[14]