CIG represent church organisations with combined investment assets of approximately £21 billion including the investments of the Church of England and the Methodist Church.
They invest in various companies and therefore have a say on decisions the companies make.
However, they will now vote against various companies if they do not appear to be progressing on issues like climate change and pay ratios.
They particularly cite issues such as gender diversity on boards and tax transparency.
The 'tougher stance' will be evident in their voting patterns, with the group threatening to vote against plans that don't fall in line with their standards.
For example, CIG members will vote against Chairs of FTSE 350 and Russell 50 companies with a score of zero for tax transparency in the FTSE ESG ratings and against Chairs who have a poor score when it comes to trying to reduce their emissions.
Christian organisations will also vote against Chairs who do not have at least one female director on their board and companies which do not disclose the pay ratio between their CEO and the average employee.
They'll also require FTSE 100 companies to be a Living Wage acredited employer if they're going to support their remuneration reports and will not support remuneration reports where the CEO receives a pension payment of more than 30% of salary.
Edward Mason, part of the Church Investors Group and Head of Responsible Investment for the Church of England Commissioners told Premier: "We have this template every year for our voting at company AGMs and each year we review it.
He spoke about the amount of leverage the Church Commissioners have:
"We hold about 1000 companies globally so all these companies have AGMs and we can excerise our vote at those...it's one of the most exciting ecumenical initiatives in church investment".
"These are issues where we feel we can work with companies through our voting through our engagement and encourage performance but I mean, yes, ultimately we can always divest from a company if it's not moving in the direction that we want to see them going".
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