While the decision to build his museum in downtown Los Angeles has not yet been finalized, Eli Broad has gone forward with the process of selecting an architect.

The Los Angeles Times reported that the billionaire philanthropist, whose new building will house his collection of 2,000 postwar and contemporary artworks, has narrowed down the shortlist of potential firms.

New York-based Diller, Scofidio & Renfro, designers of the 2006 Institute of Contemporary Art in Boston, and Dutch architect Rem Koolhaas and his firm Office for Metropolitan Architecture, are the frontrunners in the competition.

Six firms, four of them Pritzker Prize-winners, had submitted preliminary designs last week for a proposed site on the corner of Grand Avenue and 2nd Street.