Who is the biggest owner of BlackRock?

Could you please elaborate on the identity of the largest shareholder of BlackRock? I'm curious to know who holds the most significant stake in this prominent financial institution. Could you provide some insight into their background and the potential influence they might have within the company? Also, I'm wondering if there are any publicly available resources that offer more detailed information on BlackRock's ownership structure? Thank you for your assistance in addressing my questions.