Complex sentence: The company was sold to the Sumitomo corporation in the late eighties, but continued to be run largely by the same management, it is now part of the Bayer corporation, which markets the best of its brands.
Split into simpler sentences: The company was sold to the Sumitomo corporation in the late eighties, but continued to be run largely by the same management. It is now part of the Bayer corporation, which markets the best of its brands.