Ashurst is in line to secure a major advisory role on the flotation of Debenhams which is set to go ahead as early as April and could value the department store chain at £3bn.
The silver circle firm is understood to be advising the underwriters Citigroup and Merrill Lynch, which have been chosen as global coordinators for the IPO. The deal is a significant coup for the firm, which has not traditionally acted for financial advisers on IPOs.
Morgan Stanley and CSFB will be bookrunners for the flotation.
Freshfields Bruckhaus Deringer is understood to have scooped an instruction from Debenhams on the planned flotation.
The magic circle firm has represented Debenhams on its corporate deals since 2003, when it acted for a buyout consortium on its successful £1.74bn takeover of the department store.
Ashurst advised Debenhams on the deal, but Freshfields edged the firm out on future transactions following its work for the consortium, comprised of Texas Pacific, CVC Capital and Merrill Lynch Private Equity
Debenhams is expected to float from its first-half figures to the end of February, but it has not ruled out a sale of the business.
Ashurst and Freshfields declined to comment.