The National Association of Pension Funds (NAPF) says shareholder rebellion in 2012 has had a demonstrable impact on remuneration policies at some of the UK's largest companies, and is now calling for investors to exert similar pressure over issues such as auditor tenure.

NAPF, which represents 16m people in 1,300 workplace pension schemes with assets of around £900bn, has published its first AGM Season Report which it says will form the basis of an annual monitoring exercise.

Its analysis shows that most companies who faced significant rebellions by their shareholders in the 'shareholder spring' of 2012 have listened and learned. However, the report highlights ten FTSE 100 and 250 companies which, having received a warning from shareholders last year, received more than 15% dissent (votes against and abstentions) on their remuneration report in 2013.

Of these, Afren was the only company so far this year to have its remuneration report voted down by its shareholders, with nearly 75% voting against, while A. G Barr, Babcock, Easyjet, Immarsat, WPP and W S Atkins all feature on the list.

Joanne Segars, NAPF chief executive, said: 'The good news is that most companies are making efforts to improve the disclosure of their remuneration practices and to ensure their policies are driving appropriate performance. We are also pleased to see that many companies are responding positively to the increasing expectations of investors for audit committees to safeguard the independence of the external auditor.'

NAPF's analysis indicates that votes this year from shareholders failing to support auditor resolutions have risen again, although it says continue to remain very low, at approximately 3.6%. The report lists what NAPF calls 'four significant rebellions', at Pennon Group, Inmarsat, Unite Group, and Laird, where it says investors objected to the high levels of non-audit fees paid to Big Four firms.

The report states: 'Looking ahead, we encourage those companies where non-audit fees remain consistently high or where the external auditor has been in place for a lengthy period to follow the path set by others this year and take appropriate steps to ensure that the independence of their audit is safeguarded.'

However, NAPF is critical of the quality of reporting in this area and says over a third of firms in the FTSE 100 are neither stating the number of years they have been with their current auditor nor the year when the tender last took place. The exceptions it cites are Barclays, Greggs, Ladbrokes and Marstons, all of which have longstanding relationships with Big Four firms and have communicated plans to submit the audit function to tender in the coming year(s).