Lehman Brothers' involvement with Carrgran, the bidding vehicle considering whether or not to have a tilt at Arnotts, is not its first foray into the department store sector this side of the Atlantic.

The US financial house is also providing the financial backing for the proposed takeover of Allders, Britain's fourth-largest department store chain. Lehman has teamed up with London property group Minerva and former BHS and Debenhams boss Terry Green to make an offer for the company, which it hopes to put on the table before Christmas.

The Allders bid is of interest in the Arnotts context, not just because of Lehman's involvement. Analysts note the £124 million (€195 million) offer values Allders at 14.5 times prospective earnings. Meanwhile, Hong Kong businessman Dickson Poon's successful offer for the 200-year-old luxury department store chain Harvey Nichols was pitched at 16 times earnings.

By contrast, the €11.50 offer Carrgran made for Arnotts in June puts Ireland's leading department store on a multiple of just 12.5 times next year's earnings. The offer also represented a slight discount to Arnotts's prospective net asset value of €11.72.

If Carrgran and Lehman want to be taken seriously by the Arnotts board and the company's shareholders, they're going to have to stump up a bit more.