Berkshire Hathaway CEO Warren Buffett arrives to attend the annual Allen and Co. Sun Valley Media Conference in Sun Valley, Idaho, US, July 5, 2022. (BRENDAN MCDERMID / REUTERS)

TOKYO – Berkshire Hathaway Inc, run by billionaire Warren Buffett, has raised its stakes in each of Japan's five biggest trading houses by at least 1 percentage point to more than 6%, regulatory filings showed on Monday, sending shares higher.

Berkshire's stakes have increased to 6.59% from 5.04% in Mitsubishi Corp, to 6.62% from 5.03% in Mitsui & Co Ltd, to 6.21% from 5.02% in Itochu Corp, to 6.75% from 5.06% in Marubeni Corp and to 6.57% from 5.04% in Sumitomo Corp

The move is line with Berkshire's statement in 2020 that its investments in the Japanese trading houses were for the long term and the stakes could rise to 9.9%.

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Berkshire's stakes have increased to 6.59% from 5.04% in Mitsubishi Corp, to 6.62% from 5.03% in Mitsui & Co Ltd, to 6.21% from 5.02% in Itochu Corp, to 6.75% from 5.06% in Marubeni Corp and to 6.57% from 5.04% in Sumitomo Corp.

The news boosted shares of the five trading houses, led by Mitsubishi and Marubeni, which were up more than 2% in morning trade, while the benchmark Nikkei index was nearly flat.

Japanese regulatory rules require disclosure within five business days when an investor who owns more than 5% of a listed company raises or cuts a stake by 1 percentage point.

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Berkshire's increased investments in the trading houses come as it this month bought more than $4.1 billion of stock in Taiwan Semiconductor Manufacturing, a rare significant foray into the technology sector by the conglomerate.