The world's top job services firm said this afternoon it had unearthed accounting irregularities that would delay its 2003 results.
As markets immediately compared Adecco's scantily worded disclosure of bookkeeping problems to a wave of accounting scandals that has rocked the business world and sent investors scurrying, the firm's stock plunged as much as 48 per cent.
By 12.30 (Irish time), shares in the Swiss-based firm, which places 650,000 people on assignment each day for clients including French car maker Renault and IBM, were down 44.2 per cent at 45.50 Swiss francs, compared to Friday's close at 81.80 Swiss francs.
The loss wiped out last year's 47 per cent share-price gain made on the back of hopes that a global economic recovery would benefit the firm's sprawling temp business.
Adecco refused to disclose details of the irregularities it had found in an internal review, leaving dealers to worry the issue could balloon into an accounting scandal similar to those at Enron, Ahold and Parmalat, where billion-dollar frauds have led to criminal investigations.
Adecco said legal reasons prevented it from saying more than was in its initial 14-line statement on a delay in the release of 2003 earnings, but some analysts said the issues might be connected to the March 2000 acquisition of US jobs firm Olsten.
Analysts wondered whether looming depreciation charges related to the purchase for some $1.6 billion could be behind the problems.