The Dutch group posted net sales of 13bn euros and said the weak dollar had impacted on the figures.
Ahold noted that fees for lawyers and external advisors from the probes, which began in February, would be in “excess” of 100m euros in 2003.
Third quarter sales at its foodservice operations in the US and Europe fell 7.3%, while Albert Heijn store sales slid 3.3%.
For the first nine months of the year group sales slumped 10.5% to 43.3bn euros.
European retail edged up 1.3%, US retail - Stop & Shop, BiLo, Giant, Bruno's and TOPS - fell 14%, total foodservice was down 15.2% and in Asia retail sales declined 17.7%.
Earlier this month Ahold reported a 1.2bn euros loss for 2002.