Berkshire Hathaway (NYSE: BRK-B) leader and legendary investor Warren Buffett just doesn't do technology. But he does understand and invest in great companies. Say hello to IBM (NYSE: IBM), the latest addition to Buffett's investment portfolio in a sneaky little $10.5 billion accumulation campaign.

I don't know tech; I do know great businesses
More than 13 years ago, as the tech bubble was just getting inflated, Buffett told shareholders that he admired Microsoft (Nasdaq: MSFT) founder Bill Gates but wouldn't invest in his company. "I don't know what [technology] will look like in 10 years. Technology is something we just don't understand, so we don't invest in it."

Mr. Softy has underperformed the Dow Jones Industrial Average (INDEX: ^DJI) since some those comments were made in late May 1998. Big Blue, on the other hand, has more than tripled in value and handily crushed the market.

So why is the Oracle of Omaha getting on the IBM bandwagon today? After going through his subsidiaries' data-center operations, IBM's business came out looking strong. But more importantly, he's simply impressed by management's candid conversation with shareholders.

Buffett told CNBC about the "terrific reverence" with which IBM treats it investors. "They're honest with their shareholders. They tell their shareholders what they expect to accomplish, they expect to be held to it." And it's done in great detail: "They laid out some very specific things they expected to accomplish. I really compliment the management on that."

Anything you can do, we can do better
That attitude is rare in tech circles. Apple (Nasdaq: AAPL) bends over backwards to keep its intentions secret, for example. Microsoft also likes its business proprietary, patented, and held close to the vest. Even Google (Nasdaq: GOOG), which was built on open technologies, still doesn't tell us simple facts like how much money (if any) YouTube is making.

The clearly communicated strategy involves "exiting commoditized segments while increasing its presence in higher-value areas such as services, software, and integrated solutions." It's a long-term move away from "point products" and toward "integrated solutions," where IBM gets to sell a whole stack of solutions to every customer.

The success of this not-so-secret strategy has invited carbon copies, of course. Oracle (Nasdaq: ORCL) is perhaps the most successful imitator, but there's still nothing quite like the original. How much of Apple's phenomenal success comes from its top-secret policies and how much from plain old great execution? We'll never know, but IBM is showing us that you can win in business while playing an open hand of cards.

In fact, Buffett believes that IBM's openness would be exceptional in any industry. "I don't know of any large company that really has been as specific about what they intend to do and how they intend to do it as IBM," he said. "They did that five years ago, and they've done it ever since."

Business is one thing, investing is another
The investment itself was something less than candid. Buffett has been buying IBM shares since March, probably asking the SEC for permission to keep the transactions under wraps along the way. Moreover, Berkshire hasn't "talked to anybody at IBM whatsoever" about becoming one of the company's largest shareholders. This is news for IBM.

With a 5.5% stake (which triggers requirements for SEC disclosure of 5% ownership), Berkshire catapults past second-largest investor BlackRock and runs neck-and-neck with big Kahuna State Street. With the cat out of the bag, IBM jumped as much as 1.3% on a gloomy market morning.

I'd imagine that opportunistic investors would have latched onto Buffett's Big Blue plans to drive prices higher and create a larger price boost than that, had his actions been known. Keeping this market-moving investment under wraps as long as possible may not match the qualities that drew Buffett to IBM in the first place, but it's admittedly smart money management. Now Buffett says that he's "done" buying IBM unless surplus Berkshire capital happens to meet low IBM prices again.

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