Eureka Funds Management, which oversees the Commonwealth Superannuation Corporation (CSC) fund which owns the building, has invested large amounts of capital to maintain the building's prominence.

"The fund has invested [about] $30 million capital expenditure over the past five years to ensure the asset maintains its premium status," fund manager Brett Dillon said.

"With 83,000 square metres of net lettable area, including prime Collins Street retail, it ranks among Australia's five largest office towers," he said.

The striking glass and steel building dominated by four freestanding Parthenon-sized Doric columns at the front entrance of the plush marble ground floor lists top-tier merchant banks, legal firms and investment houses among it tenants.

The tower is half owned by CSC and the Public Sector and Commonwealth Super Schemes (PSS/CSS) via an unlisted superannuation trust called PSS/CSS A Property Trust which is managed by Eureka,  Australia's largest privately owned real estate fund manager with about $3.8 billion under management.

The building is widely recognised as Melbourne's best business address. It was built in 1991 at the so-called Paris end of Collins Street.