SunAmerica Inc. Chairman Eli Broad is moving from his Century City skyscraper to the 12th floor of Murdock Plaza in Westwood and might be taking Mayor Richard Riordan with him.

Broad confirmed last week that he is moving into the 14,410-square-foot office space at Westwood and Wilshire boulevards. He would not confirm what many observers said makes perfect sense: that Riordan, after leaving office in June, will set up shop with his close friend in a building that also happens to be near Riordan’s Brentwood home.

“There’s no formal arrangement,” Broad said when asked about the mayor taking space on the 12th floor. “The mayor’s a good friend and he’s welcome if he wants to be there.”

Riordan could not be reached for comment.

Broad and Riordan’s friendship goes back to the 1980s, well before Riordan was elected mayor. Through the years, the two have vacationed together and have moved in the same social circles.

Broad was one of the people who urged Riordan to get into the mayor’s race back in 1992. Since then, Broad, the wealthiest person in the city, has used his tremendous civic reach and financial resources to try to remake downtown. When the Disney Concert Hall seemed doomed, Riordan turned to Broad to spearhead the fundraising. The two also teamed up back in early 1998 to launch L.A.’s bid for the Democratic National Convention. More recently, Broad and Riordan were instrumental in putting forward a plan to revamp Grand Avenue through the Civic Center.

Both Broad and Riordan share a passionate interest in improving education. Two years ago, Broad lent his backing to Riordan’s successful effort to put up a new slate of candidates for the L.A. Unified School District Board of Education.

Broad said he will have an office on the 12th floor at Murdock Plaza, from which he will continue to perform duties as chairman of the board of SunAmerica. He said he has given up responsibilities as chief executive of the financial services company, but will remain involved with investment policy, alternative investments and acquisitions. He will have five or six SunAmerica employees with him in the new digs, Broad said.

Also joining Broad on the 12th floor will be the rapidly expanding Broad Foundation, which operates with $200 million donated by the family to improve governance, management and finances at the 65 largest urban school districts across the United States.

Broad has dedicated 3,000 square feet of display space for the Broad Art Foundation, which he said is out of room at its Santa Monica headquarters.

The Broad family also will have an office on the 12th floor.

A number of sites were considered, he said, including Center West across Wilshire Boulevard from Murdock Plaza.

He said renovations on the floor will begin by the second week of January and he hopes to be moved in by late March or early April.