Billionaire investor Kirk Kerkorian’s Tracinda Corp. is increasing its stake in General Motors Corp. to 9.53 percent, according to a Thursday filing with the Securities and Exchange Commission.

In three separate private transactions starting Aug. 23, Beverly Hills-based Tracinda bought 13.135 million shares for $463 million. When the final transaction closes Sept. 6, Kerkorian’s total ownership of General Motors stock will total 58.3 million shares.

On May 4, Tracinda announced a tender offer to pay $870 million to buy up to 28 million shares, or nearly 5 percent of total General Motors stock. But when the offer period expired on June 7, Tracinda purchased 18.9 million shares, leaving it 9.1 million shares short of the stated goal. With these purchases, Tracinda will exceed its original goal of owning more than 50 million shares, including past holdings.

According to Thursday’s filing, Tracinda purchased 5 million shares on Aug. 23 for $35 per share in a transaction that closed Aug. 26. It purchased another 5.135 million shares Aug. 30 for $35.71 per share in a transaction to close Sept. 2. A final 3 million shares were purchased for $35 million on Aug. 31 in a transaction to close Sept. 6.

Tracinda is using cash from a $400 million credit facility it set up with Bank of America to fund the investment. The disclosures were made in an amended 13D filing with the SEC.

Tracinda is the majority owner of casino and hotel chain MGM Mirage.

GM shares dropped 3.6 percent to settle at $32.97 on the New York Stock Exchange on Thursday.