The study looked at how ownership structure affects the performance of private companies in China. They analyzed data from 283 private companies listed on two exchanges from 2008 to 2010. The researchers found that having a concentrated ownership structure, especially with the top five shareholders, can help improve a company's performance. Unlike state-owned companies, the proportion of shares held by the state or corporations doesn't have a significant impact on private company performance. Tradable shareholders don't have much influence on how well a company does either.