Caliburn Partnership, the biggest of the independent corporate advisory firms in Australia, agreed to sell itself to Greenhill & Co of the US in a deal with a notional current value pushing $200 million.Greenhill, a US-listed firm that also undertakes corporate advisory work only, will issue 1.1 million shares, with a value of around US$91 million, to the current owners (partners) of Caliburn. .The partners will be able to earn another 1.1 million shares in Greenhill, which vest in three years and five years if they meet revenue hurdles of $50 million a year.Caliburn produced revenue of $68 million in 2009, down from $81 million in each of 2008 and 2007.Both Caliburn and its new owners must expect revenue opportunities to increase as larger businesses in Australia and elsewhere reposition in the wake of the global financial crisis.Greenhill needs to extend its reach into Asia to better compete with the major Wall Street and European houses that dominate the corporate advisory world.Caliburn's 40 staff will remain with the firm and the six key staff will become managing directors of Greenhill, including the firm's founders Peter Hunt, Ron Malek and Simon Mordant.Greenhill likes to style itself as the only corporate advisory firm that makes a living from this line of work alone.Other Wall Street independents (including Moelis & Company, which is recruiting in Australia) are choosing to build additional revenue steams in capital markets, asset management and private banking.