Warren Buffett Reveals $904M Berkshire Hathaway Stake In Amazon

The legendary investor told CNBC earlier this month he felt like an idiot for not buying Amazon earlier. But he also recently said he doesn't think he understands the cloud market that Amazon leads through its most-profitable division, AWS.

Like many less-astute investors, Warren Buffett feels like an idiot for not having bought Amazon stock a long time ago, he told CNBC earlier this month.

But Buffett's company, Berkshire Hathaway, is now a significant Amazon shareholder, with a $904 million stake in the e-commerce giant after the market closed Wednesday.

That position of 483,300 shares at the end of the first fiscal quarter on March 31—about .1 percent of total Amazon equity—was revealed Wednesday in an SEC filing.

[Related: Warren Buffet’s Berkshire Hathaway Dumps Oracle Stake]

While Buffett has repeatedly expressed his admiration of Amazon and founder Jeff Bezos, he's also admitted a lack of understanding about the industry led by the company's most-successful and profitable business, Amazon Web Services.

In February, the “Oracle of Omaha” told CNBC that Berkshire Hathaway's exit from a $2.13 billion investment in Oracle was driven by his confusion around the state of the larger cloud industry, even as he sees the top providers enjoying massive success.

"I've been amazed at what Amazon has done there, and now Microsoft is doing as well. I just don’t know where that game is going," Buffett said.

A previous investment in IBM colored his view of the cloud market, and of holding Oracle for the long haul.

"I don’t think I understand exactly where the cloud is going," Buffett said in February.

In 2011, Berkshire bought $10.7 billion of Big Blue at roughly $170 per share, then six years later offloaded most of that position at a loss.

On May 2, Buffett told CNBC that his company had bought Amazon, but it was "one of the fellows in the office that manage money" that made the investment, not him.

"Yeah, I’ve been a fan, and I’ve been an idiot for not buying" he said in that interview.

Berkshire Hathaway also disclosed to the SEC on Wednesday it now holds 5.1 million shares of Red Hat, which represents an increase in its position by 22 percent since last reporting.

Red Hat closed Wednesday at $185.28. IBM is looking to finalize a deal later this year in which it will buy the open source software powerhouse at $190 per share.