Are we entering an age of celebrity activism?

Until recently, the following formula was true of almost all activist investing campaigns: borrow money from outside investors, buy as big a stake as possible within legal and financial constraints, seek to persuade as many other investors as possible to back your campaign, and ultimately sell your stake for a profit.

In recent years, the popularity of ESG activism has added some nuances. Jeff Ubben launched an impact fund, Chris Hohn started a campaign asking companies to address climate change. But both couched their arguments in economic terms and took on outside investors. Chris James set up Engine No. 1 and spent almost as much on a proxy contest at Exxon Mobil as on the stake itself, although he presumably made money both on the investment and the fundraising he was able to do on the back of the favorable press it generated.

This year’s defining campaigns have flipped the script.

At McDonald’s and Kroger, Carl Icahn is likely to spend way in excess of the stakes he has accumulated to pressure each company into the ending of gestational crates for pregnant sows – animal welfare reforms that have hitherto generated little interest from Wall Street.

Over at Twitter, Elon Musk has put rather more of his fortune at stake for a takeover bid he claims is about “the future of civilization” and “not a way to sort of make money.”

Has the ESG revolution in activist investing created something unexpected? A class of billionaires that don’t need outside investors and are willing to use a playbook of activist investing tools as a soapbox for issues they care about who can acquire a stake and run a proxy fight for as little as $10 million, generating huge public interest in the cause.

Billionaires wanting to influence the world still have the traditional options of channeling money into philanthropy or politics, but shareholder activism is becoming an increasingly popular way to set public policy, with a lower reputational risk than hitherto.

“What we have are high-visibility, high-powered, high-wealth individuals who’ve earned a tremendous amount of clout and credibility and want to put it to use,” Andrew Freedman, co-head of Olshan Frome Wolosky’s activism practice, told me this week. “We’re seeing an evolution of the same tools used to catalyze operational and governance changes to catalyze do-good or environmental and social causes that for whatever reason might be slipping off the radar-screen of boards.”

“It’s a wakeup call for boards that might have been reticent to address those issues because they weren’t necessarily about profitability,” Freedman continued. “They need to be thinking about and taking these actions on their own and they’re not necessarily going to be penalized if it’s the right thing to do.”

Chris Davis, chair of Kleinberg Kaplan’s M&A and investor activism groups, says Musk and Icahn are “automatic good copy” for journalists, but “the individual billionaire angle” may be less important than “the bigger movement – that ESG is increasingly a winning strategy in an activism context.”

“It’s possible that the individual billionaire with money to burn is a developing story,” he told me this week. “Are there enough billionaires with enough free money to really change the landscape? I don’t know, I think that remains to be seen.”

True, there are few individuals as rich or unconventional as Icahn or Musk. But someone somewhere could be taking notes.

“You’re talking about two people who in different ways are one of a kind,” said Derek Zaba, co-head of shareholder activism at law firm Sidley Austin, in an interview. “Will we see these types of campaigns next year? It’s impossible to know – depends what’s going on in their heads.”