Prof Mayer says that global crises such as the environment and growing inequality are forcing a reassessment of what business is for.
"The corporation has failed to deliver benefit beyond shareholders, to its stakeholders and its wider community," he said.
"At the moment, how we conceptualise business is, it's there to make money. But instead, we should think about it as an incredibly powerful tool for solving our problems in the world."
He said the ownership structure of companies had made the UK one of the worst examples of responsible capitalism.
"The UK has a particularly extreme form of capitalism and ownership," he said.
"Most ownership in the UK is in the hands of a large number of institutional investors, none of which have a significant controlling shareholding in our largest companies. That is quite unlike virtually any other country in the world, including the United States."
This heavily dispersed form of ownership means none of the owners is providing a genuinely long-term perspective on how to achieve goals while also making money.
Mars chairman Stephen Badger admits things are different now.
"We've never felt the need to be public but times have changed," he said.
"The talent [employees] really want to know what the company they work for, stands for.
"Equally important is that the magnitude of the challenges facing the world - climate change, poverty, biodiversity loss - these are issues that we care deeply about.
"We've got less than 10 years to get this right - incremental change is not enough. We are prepared to spend serious money on this and if that means lower profits, so be it. Whatever it takes to get the job done,"
The challenge to companies is threefold. Staff who want to believe in the company they work for, consumers who may boycott the products of companies that don't get it and, of course, politicians who may legislate, tax or nationalise them out of existence.
But we should be cautious about announcing the death of shareholder power.
Unilever - the Anglo-Dutch makers of Marmite, PG Tips and 400 other consumer brands - has long been admired for its enlightened approach to its societal impact. In 2017, it received a surprise takeover bid from Kraft Heinz.
Its response was to accelerate the sale of some businesses, increase its dividend, cut costs by 12%, raise the amount of debt in the company and give a further €5bn to shareholders through share buybacks. Steps the then chief executive, Paul Polman, now says he would rather not have taken.
"Feel free to be responsible - but don't be complacent about the interests of your owners" was the clear message and lesson learned.
Alan Jope, the current Unilever chief executive, told the BBC that its focus on doing right by society and the environment was not out of fear of nationalisation, taxation or regulation, but out of fear that its products would be shunned by a new generation of consumers unless they got this stuff right.
Is that doing the right thing for the wrong reason? Not really. Does it matter if it is? Probably not.
Unilever's Mr Jope did have a supportive message for the Labour Party. When asked if he supported company law changes to discourage firms from placing shareholders above others, he gave a clipped and clear response: "Yep."
One thing is certain. No matter who wins the UK election, you can expect to hear the word "purpose" a lot in the next few years.
There is only one boss. The customer. And he can fire everybody in the company from the chairman on down, simply by spending his money somewhere else.