Boston-based Grantham, Mayo, Van Otterloo & Co (GMO), a privately held investment management firm for institutional investors with $25 billion of assets, has just incorporated in Singapore. This marks its first physical foray into Asia ex-Japan, although the firm opened a Sydney office in 1996, and has managed Japanese securities since 1986. The partners founded it in 1977, and it also has offices in London and San Francisco.