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Buffett’s big idea for better M&A advice

Berkshire Hathaway hasn’t done a big deal in years, as Warren Buffett explains in his latest annual letter to shareholders. Even so, he’s happy with his track record. Likening mergers to marriages, the legendary investor writes, “I would say that our marital record remains largely acceptable, with all parties happy with the decisions they made long ago.”

He thinks others could do better. There is the ever-present risk of succumbing to “Wall Streeters bearing fees,” as he describes deal-hungry investment bankers. “At many companies, these super-salesmen might win,” he notes. “I do not, however, expect that to happen at Berkshire.”

“Independent” directors, in particular, aren’t serving companies well, he says.

• When it comes to acquisitions that C.E.O.s want to make, independent directors are supposed to check their impulses. But corporate chiefs rarely bring in outside advisers who provide dissenting opinions, so the deals usually happen. “When seeking directors, C.E.O.s don’t look for pit bulls,” Mr. Buffett writes. “It’s the cocker spaniel that gets taken home.”