Remember that time vocal bank analyst Mike Mayo was "exiled" from Wall Street?
He's now trying to get back in—by buying up shares in bank stocks, an effort to gain entre to key investor meetings usually closed off to analysts.
The practice of analysts getting intimately familiar with companies in their coverage isn't entirely uncommon: Financials analysts have long opened multiple checking accounts or certificates of deposit across all banks, in order to test out the product.
But what Mayo, now an analyst at Credit Agricole, wants is access, and not to every bank: Mary Beth Kissane, a spokesperson for Mayo, confirmed that he only has a few investments. Among those investments, Mayo holds 100 shares in each of Citigroup, Morgan Stanley, State Street and KeyCorp.
At JP Morgan Chase's Feb. 26 investor day, the bank's shareholders were buzzing about the terse dialogue between Mayo and the bank's chairman and CEO, Jamie Dimon. At one point, Mayo questioned whether Chase customers would take their business to another bank with higher-than-necessary capital levels, like UBS.
Dimon, incredulous that Mayo would think Chase would lose business for that reason, remarked: "That's why I'm richer than you."
The multiple barbs traded led other investors to question whether Mayo's new "buy side" positions included JPMorgan (they don't).
Kissane called his positions "de minimus," but also "unique" and "activist"—not ruling out the idea that Mayo could take his trademark bulldog style from the analyst page to the shareholder proxy.
In Mayo's 2012 book, "Exile on Wall Street," Mayo detailed his frustration with the banking sector, which he claimed closed off access to him because of his cautionary and contrarian opinions.
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"I get frustrated with banks—I get furious at times—because banks should hold themselves to a higher standard," Mayo wrote in "Exiled."
Now, as a shareholder, he can air his frustrations.
-By CNBC's Kayla Tausche; Follow her on Twitter @kaylatausche