Complex sentence: Bertelsmann took over control in 2007, and a year later, sold its interest to Najafi Cos, an Arizona investment firm, which held its ownership in a subsidiary named Direct Brands, which also held its ownership in the Columbia House record club.
Split into simpler sentences: Bertelsmann took over control in 2007, and a year later, sold its interest to Najafi Companies, an Arizona investment firm. Najafi held its ownership in a subsidiary named Direct Brands, which also held Najafi's ownership in the Columbia House record club.