An official statement said that the bid had been rejected unanimously because it represented "a significant undervaluation of Nisa-Today's and would have meant demutualisation of the company".
A counter statement from Bibby said that the offer was worth over £1,000 per share, with "an opportunity to retain ownership in the business".
However, industry insiders believe the takeover bid was made as a defensive measure because Bibby is on the brink of losing its distribution agreement with Nisa-Today's. Sources expect DHL to be awarded the ambient distribution contract for the group to go with its existing supply deals for chilled and frozen lines within a matter of weeks.
One Nisa retailer who asked not to be named told C-Store that members were 100% against any sale of the company: "Trading is really positive at the moment and growth has been strong for a number of years despite many major retailers leaving the group. There's no need for any major capital injection and no appetite to abandon mutual status."
A new distribution deal could however create complexity within the group, as Bibby owns 51% of Costcutter, which accounts for 40% of Nisa volume.
Nisa Today's is to return £500,000 in trading surplus to members this month. Group sales reached a record level of £1.27bn for the year ending march 2009, up 11% on the previous year.