Rabble-rousing bank analyst Mike Mayo is down but not out.

After learning during a half-hour meeting late Monday that his brokerage firm, CLSA, was shutting down its U.S. stock-analysis unit immediately, Mayo showed up early the next morning at JPMorgan Chase's (JPM - Get Report) annual investor conference, where he peppered executives with questions, identifying himself as "a free agent analyst." Later in the day, CEO Jamie Dimon publicly lauded his doggedness.

Then on Wednesday, Mayo, 53, took the next step toward his future. He visited a Charles Schwab branch in midtown Manhattan to buy at least two shares of every bank he covered, from Bank of America (BAC - Get Report) to Zions (ZION - Get Report) , he said. The motivation? So he can have the option of attending their upcoming annual meetings as a shareholder, as he's done several times in recent years. Last year, he flew to Charlotte, N.C., to needle Bank of America CEO Brian Moynihan over perceived corporate-governance shortcomings.

"It's my ticket for admission," Mayo said by mobile phone of his stock purchases, shortly after emerging from the Schwab branch. "I'm not going away."

CLSA, a Hong Kong-based unit of the Chinese investment bank Citic Securities, said Monday in a statement it was closing Mayo's unit amid "declining revenues in equity research" and would refocus the U.S. business on trading services. The firm will continue to provide research on Asian stocks.

The news came as a shock to Mayo. But he's no stranger to change. According to regulatory filings, he's worked for at least six brokerage firms in the past 25 years, including UBS (UBS - Get Report) , Lehman Brothers, Credit Suisse (CS - Get Report) , Prudential Financial (PRU - Get Report) and Deutsche Bank (DB - Get Report) . He had been at CLSA and its predecessor firm since 2009.

Mayo started attending annual shareholder meetings in recent years, he said, because the gatherings offer a "once-a-year opportunity to hold the board of directors accountable," with management in the room.

"It creates a little bit more tension," Mayo said. "No one likes being quizzed in front of their bosses."

Among the shareholder gatherings he's attended: New York-based JPMorgan's, in Tampa; one that New York-based Citigroup (C - Get Report) held in St. Louis; State Street's  (STT - Get Report)  in Boston and KeyCorp's (KEY - Get Report) in Cleveland.

He's also gone to Morgan Stanley's (MS - Get Report)  meeting in New York several times in the past few years. In the early 2010s, he says, he put a buy rating on the stock, even as he pressed CEO James Gorman to make major changes to the investment bank's strategy. The shares have since tripled.

"I'm in the second half of my life, and I find what I value is holding truth to power," Mayo says. "I'll put my three-decade stock-picking record against anyone's." 

The analyst says he's attended Bank of America's meetings so many times that he's gotten to know several of the individual shareholders who go regularly, including an elderly couple who give him updates on their grandchildren.

Investors might want to keep an eye on Mayo's travel schedule.

Last year, his public campaign to push Comerica (CMA - Get Report) to take more drastic steps to shore up profitability culminated in a trip to Dallas in April to grill CEO Ralph Babb and the board of directors at the bank's annual meeting.

Comerica later announced plans to slash expenses by cutting 9% of its nearly 9,000-person workforce. The company's shares surged, ending the year up 63%, the top performer among large and mid-size U.S. banks. (It also helped that oil prices rose, easing pressure on the bank's ample portfolio of energy-industry loans.)  

Mayo says he doesn't know what he's going to do next. He's open to working at another brokerage firm, possibly starting his own, or working in money management.

Nor does he know which companies' annual meetings he'll attend this year. Possibly Bank of New York's (BK - Get Report) . Maybe Morgan Stanley's again. The point is to keep going.

"We'll see," Mayo said. "It'll have benefits wherever I land."

He added: "I still need to get a job."

Fortunately, he already has a brand, as Dimon pointed out: "You didn't need CLSA," the CEO told Mayo during a question-and-answer session.

"We've known each other a long time," Dimon added, recalling that when he joined JPMorgan predecessor Bank One as CEO in March 2000, he was told Mayo wasn't allowed on analyst calls because of a lengthy and "terribly insulting" assessment of the company titled Even Hercules Can't Fix It.

"I told the management team, "I hate to tell you, read his tome,'" Dimon recalled. "'He is right about every single thing in there. And that's how you become better, not by sticking your fingers in the eyes."

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