Leading asset managers and insurers have donated more than £90,000 to a parliamentary group on corporate governance.
The corporate governance APPG is a cross-party group of MPs and Lords chaired by Lord Myners designed to "influence and develop understanding of corporate governance through the promotion of a culture based on responsible leadership and investment".
It received donations between £1,500 and £14,000 from companies and investment firms, including £2,000 from Hermes, £5,000 from Fidelity, £5,000 from Legal & General, £10,994 from BNY Mellon, £10,000 from M&G and £7,500 from PricewaterhouseCoopers.
The data, revealed in Guardian research into all-party parliamentary group funding, will raise concerns about the lobbying influence and access of financial services firms.
Transparency campaigner Heather Brooke who first pursued the MPs' expenses scandal told the Guardian: "The public has a fear that politicians are unduly influenced by people with money, and they need to work to tackle this perception.
"Currently, because of the opacity of funding, these groups create the perception of lobbying through the back door. If they want to be seen as a respectable part of parliament, they should disclose more information on their activities and funding.
"If they are not willing to do this, we really have to wonder why - what have they got to hide?"
The corporate governance group's website lists opportunities for sponsors to "join the debate" on corporate governance including participating in seminars and exclusive networking events, attending and participating in four annual policy meetings "open only to an elite group of members and sponsors", enjoying joint branding on group's website and literature and "access key journalists who make up the APPCGG's exclusive media communications group."
A PwC spokesman said the firm did not consider the sponsorship as a political donation and said the money had been used to fund roundtable events and discussion forums on corporate governance.
He said: "We do not make cash donations to political parties but we do support the public policy process through essentially offering our people's time and expertise to support public policy work for political parties.
"The reason we support the APPG on corporate governance is we have a strong interest in debate on corporate governance matters. As far as we are concerned that is not a political donation.
"That is a donation to a discussion forum that happens to be an all-party group of MPs."
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