The Standards and Privileges Committee found that although Mr Maude had listed his interests in the official register, he should have mentioned them again when he signed a motion or amendment.
Complaints against Mr Maude concerned his directorships of the supermarket chain Asda and of Gartmore Shared Equity Trust (GSET).
The shadow chancellor failed to put the required "R" by his name to denote a registered interest when signing a motion on PEPs and ISAs and when promoting a new Finance Bill clause on the retail trade.
Mr Maude accepted he should have declared his Asda directorship but said his name had been routinely attached to the clause as a member of the Conservative front bench.
He also argued that GSET did not trade in PEPs or ISAs, but the Parliamentary Commissioner for Standards, Elizabeth Filkin, found that a closely related firm, Gartmore Investment, did do so.
She accepted that Mr Maude's transgression had been unintentional, but added it was members' responsibility to ensure they complied with the rules. The Standards and Privileges Committee decided no further action should be taken against Mr Maude.
The complaints were brought by two Labour MPs, Christopher Leslie and Geraint Davies. Last night Mr Leslie said that ignorance was no defence. "The question is, how many other things go on without his knowledge? I personally think he should come and apologise," he said.Reuse content