Investment Group Raises Holdings in Unilab Corp.

An investment group including international money manager George Soros raised its stake in Tarzana-based Unilab Corp. to 8.63% of the lab-testing company.

The investment group, led by Dallas-based GHS Management Inc., bought 146,000 Unilab shares between May 8 and Nov. 29, bringing its holdings to 2.71 million shares, according to a filing with the Securities and Exchange Commission.

Previously, GHS held 2.57 million Unilab shares.