AIMS Securities has won the approval of MacarthurCook's board to take over the company after it raised its bid and promised to retain the property fund manager's staff.

AIMS offered a new bid of 43 cents per share, 8 cents higher than its previous bid.

"We are pleased that AIMS has recognised the increased value in MacarthurCook and welcome its desire to continue to build MacarthurCook into a leading international funds management business," MacarthurCook chairman Richard Haddock said.

Earlier this week MacarthurCook rejected AIMS' previous bid of 35 cents per share, saying the offer undervalued the company.

But Haddock acknowledged that an important stumbling block in earlier discussions was the uncertainty surrounding AIMS' plans for MacarthurCook's staff.

"We've had further discussions with AIMS about what their plans were for the existing organisation of MacarthurCook," he said.

"They are now committed to keeping the Melbourne office management team and Singapore office as part of what we consider to be a better enunciated strategy.

"This, together with the price they are offering, offers shareholders a better outcome."

There is no agreement on how long MacarthurCook's staff will be retained, Haddock said.

"But there is much more commitment because they have acknowledged they don't have any property management staff and that is not an easy thing to build up," he said.

The support of the board for AIMS' bid makes it possible for the sale of a 15 per cent stake held by IOOF.

"The agreement with IOOF was that the shares would be locked up, as they were, unless there was a 50 percent control or a recommended offer," Haddock said.

"Now that there is a recommended offer that stake is available for IOOF to do with as they wish."

As part of the takeover AIMS will partly underwrite a $5 million capital raising by MacarthurCook.