Warren Buffett's Berkshire Hathaway posted a rare share loss during the fourth quarter of last year, the company reported on Saturday, with the conglomerate's bottom line taking a hit from its holdings in beleaguered consumer giant Kraft Heinz.

Berkshire posted a share loss of more than $15,000 in its Class A shares, and wrote down over $3 billion related to its investment in Kraft. Wall Street analysts were expecting a profit of $3,349.04 per A share, according to a forecast by Refinitiv.

Berkshire's report comes after Kraft Heinz, one of the company's biggest holdings, wrote down more than $15 billion on two of its most well-known brands: Oscar Mayer and Kraft. Kraft Heinz also trimmed its dividend and disclosed that the Securities and Exchange Commission is investigating its accounting practices.

The news sent Kraft Heinz down about 30 percent and slashed the value of Berkshire's stake in the company by more than $4 billion.

It also led to Barclays analyst Jay Gelb to slash his earnings estimate on Berkshire in half. The analyst also said in a note to clients that Berkshire's quarterly numbers will likely be impacted by "substantial catastrophe losses for the global insurance industry" due to the wildfires in California last year and Hurricane Michael.

--Reuters contributed to this article.

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