Pankaj Nangia/Bloomberg News

With his $5 billion investment in Bank of America, Warren E. Buffett is adding yet another American financial giant to his stock portfolio.

His investment vehicle, Berkshire Hathaway, has long been an investor in the nation’s banks, and counts five firms in which it has a major stake.

Here were Berkshire’s top holdings in financial companies as of June 30, according to a regulatory filing:

FIRM MARKET VALUE OF STAKE AMOUNT OF SHARES CHANGE FROM 1ST QUARTER American Express $7.84 billion 151,610,700 No change Wells Fargo $9.89 billion 352,327,608 + 9,703,683 shares US Bancorp $1.76 billion 69,039,426 No change

Source: Bloomberg News/S.E.C. filing

Berkshire also owns smaller stakes in the Bank of New York Mellon and the M&T Bank Corporation.

Of course, Mr. Buffett’s most notable bets on the finance sector of late came from his big capital injections into Goldman Sachs and General Electric during the financial crisis. Those two deals closely resemble his new investment in Bank of America; he bought $5 billion worth of perpetual preferred shares in Goldman and $3 billion in G.E.

Those purchases were highly profitable for Mr. Buffett, with the preferred shares carrying a 10 percent annual dividend, as well as requirement that Goldman and G.E. pay a 10 percent premium to buy Berkshire out. Goldman has since bought back Mr. Buffett’s holdings, while G.E. has said that it intends to do so.

Still, not all of Mr. Buffett’s Wall Street moves have turned out well. While Berkshire earned a profit from its Goldman and G.E. investments, warrants that it received along with the preferred shares remain underwater. (The 700 million warrants that Berkshire received from Bank of America, on the other hand, are currently in the money: They carry a strike price of $7.142857, while the firm’s stock price is at $7.89 as of late Thursday morning.)

Going further back, just before the market crash of 1987, Berkshire bought $700 million of Salomon Brothers preferred shares.

Related Links Buffett Invests $5 Billion in Bank of America

To protect his holdings, Mr. Buffett undertook a highly unusual move. He stepped in as Salomon’s chairman in 1991 after John Gutfreund was forced to resign following a Treasury securities bidding scandal. Mr. Buffett was widely credited with saving the firm from collapsing by quickly cleaning house and winning over angry clients, politicians and investors.

(He famously delivered the following lines in his testimony before Congress on the scandal: “Lose money for the firm, and I will be understanding; lose a shred of reputation for the firm, and I will be ruthless.”)

Mr. Buffett stepped down as Salomon’s chairman after roughly 10 months. Berkshire sold its shares in the firm in 1997, after Salomon was sold to what is now Citigroup.

Outside of banks, Mr. Buffett declined to invest in the hedge fund Long-Term Capital Management in 1993. After LTCM faced collapse in 1998 amid a global financial crisis, its officials approached Mr. Buffett — and he again passed.