Shares in CB Richard Ellis Group Inc. closed up 13 percent Monday after hedge fund Lone Pine Capital LLC increased its stake in the real estate investment trust to 6.6 percent.

The Greenwich, Conn.-based fund, run by Stephen Mandel, now holds about 13.2 million shares in the El Segundo-based firm, a filing filed March 20 with the Securities and Exchange Commission said.

Share price of the world’s largest commercial real estate firm had declined more than 13 percent so far this year prior to Monday, and is down more than 45 percent vs. March 2007.