The acceptance level had originally been set at 90%, but Huntsworth and Incept have agreed to revise it to the level of acceptances that have now been received.
It said that it expects Incepta shares to be delisted from the London Stock Exchange on May 31 this year. The merger deal was originally announced in March this year.
Incepta owns the Citigate PR brand and the Red Consultancy, along with the growing market research operation Incepta Marketing Intelligence, which includes Momentum Research Group, DVL Smith and Hauck Research.
Huntsworth was set up by Lord Chadlington, the founder of Shandwick, which is now part of Interpublic Group and known as Weber Shandwick. It owns PR agencies including Counsel, Grayling and Harrison Cowley.
Lord Chadlington will become executive chairman of the group and has agreed to stay on in a full-time capacity until at least the end of 2008, while Incepta's chief executive Richard Nichols becomes chief executive.
Francis Maud, the Tory MP and chairman of Incepta, will take the joint deputy chairman role along with Jon Foulds, chairman of Huntsworth.
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