A private equity firm has purchased a majority interest in The Generations Network (TGN, formerly MyFamily.com), parent company of Ancestry.com, DNA Ancestry, Genealogy.com, RootsWeb and others.

Spectrum Equity Investors, already a partial stakeholder in TGN, will pay $300 million for its majority interest. Two of its partners will join TGN president and CEO Tim Sullivan on the new board of directors. Other terms of the purchase weren't disclosed.

Private equity firms buy companies hoping to make money off them, and that’s probably a good bet here. The Generations Network online properties have 900,000 paying subscribers, and receive 8.2 million unique visitors and more than 429 million page views a month. According to the Internet news site TechCrunch, TGN rakes in around $150 million in revenue annually.