Morgan Stanley tops the global ranking in equity underwriting year-to-date and has its highest market share in the category in six years thanks to its role as lead bookrunner of the Treasury Department's sale of its remaining stake in Citigroup.

Morgan Stanley - which handled 2.1 billion Citigroup shares in the deal - now boasts a global market share of 8.9% within equity capital markets, up from 7.8% before the Citigroup transaction.