TOKYO, March 17 (Reuters) - Warren Buffett's Berkshire

Hathaway ( BRK/A ) raised its holdings in five Japanese trading

houses, regulatory filings showed on Monday, in the U.S.

conglomerate's latest investments in Japan's top commodity firms

that began nearly five years ago.

Berkshire's stake in Mitsui & Co ( MITSF ) rose to 9.82% from

8.09%, while its holdings in Mitsubishi Corp ( MSBHF ), Sumitomo

Corp ( SSUMF ), Itochu ( ITOCF ) and Marubeni ( MARUF ) also rose

by some percentage points, according to documents filed to

Japan's securities watchdog by its unit, National Indemnity

Company.

The filings followed Buffett's annual letter to Berkshire

shareholders last month, where he said the five trading houses

agreed to "moderately relax" limits that capped Berkshire's

ownership stakes below 10%.

"Over time, you will likely see Berkshire's ownership of all

five increase somewhat," Buffett had written.

Known as "sogo shosha", the trading houses deal in a variety

of materials, products and food - often serving as

intermediaries - and provide logistical support. They are also

involved in the shipping, energy and metals businesses.

(Reporting by Tokyo Newsroom; Editing by Muralikumar

Anantharaman)