We update this article annually because Berkshire Hathaway reports details of its subsidiaries in its annual reports. Quarterly reports may contain information about new acquisitions or sales and performance of broad categories (“insurance and other” and “railroads, utilities, and energy”) but do not contain figures for each subsidiary.
Many sites will provide quarterly updates on BRK’s holdings of publicly traded securities, but these will not generally contain information on wholly-owned or majority-owned subsidiaries that do not trade on a public exchange. Berkshire Hathaway does publish an up-to-date list of its subsidiaries but without financial information.

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