Hewlett-Packard levelled serious accusations on Tuesday against a software company it bought last year, saying it would take a $8.8bn writedown after it claimed Autonomy's leadership misrepresented its performance as the deal was being negotiated.

H-P, of Palo Alto, California, said it was writing down a vast majority of Autonomy, a software company it acquired last year for more than $10bn, due to "serious accounting improprieties, disclosure failures and outright misrepresentations" at Autonomy that occurred prior to H-P's acquisition of the firm. The non-cash write down amounted to $8.8bn, H-P said, which included recent drops in H-P's stock.