The €15bn pension fund for the Swiss mail services, PK Post, is to review its membership of the proxy voting foundation Ethos over concerns about the organisation’s governance.

Françoise Bruderer Thom, managing director of the PK Post, confirmed the plan to IPE but did not give a specific date for when the trustee board will conduct the review.

Bruderer Thom had a seat on Ethos’ trustee board until December 2017, representing one of the foundation’s largest members. She resigned together with lawyer Monika Roth, member of the supervisory board, in protest at the foundation’s governance.

Ethos was set up in 1997 by two pension funds in Geneva to provide environmental, social and governance consulting and proxy voting services. Today it has more than 200 pension provider members.

“Because I no longer want to support the [management] at Ethos and [board chairman] Dominique Biedermann is not pushing his own succession plan, I demanded his resignation as president,” Bruderer Thom told Swiss media in December.

However, Biedermann refused to resign his post so Bruderer Thom and Roth, who supported the criticisms, left.

In a reply to IPE the PK Post managing director said she “does not want to make any more public statements” on the subject.

Her criticism was directed at the management structure of Ethos. Dominique Biedermann is president of the supervisory board, which according to Swiss law has much more powers in steering the company than a mere supervisory function.

At the same time, Biedermann’s wife Yola heads Ethos’ corporate governance department. Roth was quoted by Swiss media as saying that the managing director of Ethos, Vincent Kaufmann, was “the boss of his boss’ wife”.

IPE could not reach her for a comment.

The staff arrangement at Ethos had been okayed by the boards in 2015 but was not meant to be permanent.

At Ethos, Biedermann said he was “surprised” by the attack on the corporate governance at the foundation. He told Swiss media just before Christmas that he was considering “legal action” against the two former board members.

In a statement sent to IPE he said Ethos had decided “not to communicate anything on the possible legal action” for the time being.

He confirmed the foundation has intensified its search for new board members.

Biedermann emphasised that the trust of other board members, as well as the members of the foundation, remained strong.

“There were no changes in the membership structure”, he confirmed to IPE.

Should PKPost decide to end its membership in Ethos and withdraw its 7% stake, it would still be covered for ESG consulting. Together with other major Swiss pension funds it was one of the seven founding members of the SVVK-ASIR association for responsible investing in 2015.

As of January two new members joined SVVK-ASIR: Swiss insurer Mobiliar and the pension fund for the retail giant Migros.