When investment firm Magellan’s co-founder and major shareholder Hamish Douglass separated from his wife in 2021, the media’s publication of the news was considered controversial. It was justified, in part, because it might result in the sale of a swathe of his shareholding and control of the company could change.

Douglass was never a household name outside the business community, but inside the finance goldfish bowl he was a public figure and the impact any large share sale would have on other Magellan investors was significant.

He was the talisman for his company, and many of its clients had been in his thrall. In the world of funds management, Douglass was a celebrity.

Fast-forward to this week’s news that Commonwealth Bank boss Matt Comyn is separating from his wife of a couple of decades – an event which raises the question whether, or at what point, does any executive’s private life become fair game.

From the outset that justification for disclosing Douglass’ marital status does not apply to Comyn. His stake in CBA is worth serious money to most people, inconsequential in the scheme of the $262 billion company, and the sale of any or all of his stake won’t move the dial.

But shareholders definitely want to see the most senior executive of their company with a certain degree of share ownership, so Comyn’s recent sale of $8.4 million in shares can now be understood as likely part of dealing with his personal affairs amid the separation.

Without this extra piece of personal information, CBA shareholders could become concerned that Comyn was cashing out stock and sending a signal that shares were overvalued.

(There is a reason for the ASX rules that dictate executives and directors of listed companies have to disclose any share sales).

Another argument in favour of disclosure of personal information says that shareholders have a legitimate right to know of issues that may be distracting to the chief executive’s exercise of his duties.

(That said, the outwardly unflappable Comyn has not missed a management beat – at least not publicly. Last week he delivered a strong 2026 year profit, seemingly without raising a sweat.)

The above reasoning pushes Comyn’s private news at least some ways towards passing the public interest test.

But more broadly, in this modern digital information age, Comyn is a public figure. From regular grabs on national television, to his carefully curated opinions featured in every news publication, to podcasts about what he eats for breakfast and even his exercise regime, Comyn has curated a public profile.

Part of his highly remunerated job is being the public face of CBA – the country’s largest company.

And his success in leading the bank, which has 800,000 investors, 16 million customers and 55,000 staff has landed him as a de facto proxy for big business in Australia.

His close relationship with the Albanese government and Treasurer Jim Chalmers in particular has also recognisably boosted his influence on public policy.

My fellow journalist and author of this week’s scoop, John Buckley, says there is a kind of “cult of Comyn” that extends beyond the business community.

Of course there will be a cohort of readers and Comyn supporters that understandably consider the publication of details of his personal life inappropriate or even voyeuristic.

Do they also consider the details of James Packer’s relationships to be off limits? Do they snigger each time Rupert Murdoch lands yet another wife, even in his 90s?

Mike Cannon-Brookes or Andrew Forrest or even Keir Nielson (founder of Platinum Asset Management), had publicised marital breakdowns, all of which were reported. Of course, they all had shareholdings large enough to, at least potentially, cause major changes for their companies, depending on how their separations played out.

I am sure none of them enjoyed their laundry being aired in public even if there was nothing particularly controversial about the breakdown in their marriage.

It is an unfortunate fact of life that being the public face of a major institution like the Commonwealth Bank has made Comyn a public figure and the closest thing Australia has got to a business celebrity.

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