The Nomura Holdings Inc. group became the top securities underwriter, merger and acquisition adviser in value in Japan druing the first half of 2007, according to Thomson Financial rankings covering transactions.

The stock underwriting market in the world shrank to $14.23B in the first half of this year, showing 56% decrease compared to the previous half year. Thomson said that the steep decrease happened as firms issued bonds when they saw the trend of rising of interest rates.

For Nomura, the firm handled the $1.36 billion dollar sale of Honda Motor Co. shares, the $970 million dollar public stock offering by Daikin Industries Ltd. and the $700 million sale of Japan Petroleum Exploration Co. shares.

As a result, the firm’s market share reached 46.8 percent, increasing 19.8 percentage points in the first half of the year.

The nation’s second biggest securities firm of the first half of the year is Daiwa securities SMB and the third is Mitsubishi UFJ Financial Group Inc.

Mergers and acquistions involving Japanese companies remained strong in the first half of the year, increasing 3 percent to $81.3 B.

According to Thomson Financials data, the biggest M&A deal was Citigroup Inc.’s $7.9 billion dollar tender offer for Nikko Cordial Corp. shares.