By Kosaku Narioka

TOKYO -- Japanese stocks rose to a 15-year high intraday Thursday, as investors took a renewed interest in companies that have shifted their focus back to growth and efficiency.

The Nikkei Stock Average gained 0.4% to 18,264.79, its highest intraday level since May 2000.

There are signs that Japanese companies, ranging from Canon Inc. (CAJ) to Sony Corp. (SNE), are starting to tap into their large cash piles, reinforcing their core businesses and buying out firms for expansion. These companies finally appear to be leaving behind the uncertainty that followed the 2008 global financial crisis, and the aftermath of the March 2011 earthquake and tsunami disaster.

"We are finding a lot more growth opportunities (in Japan) -- good companies that are executing well in this environment," said Nick Niziolek, who co-manages an $800 million international growth fund at Illinois-based Calamos Investments LLC. The fund, which had very little exposure to Japan for years, turned overweight on Japan in October for the first time since 2007, Niziolek said.

Domestic firms are also getting a tailwind from Prime Minister Shinzo Abe's economic policies, which have weakened the yen and generated mild inflation. The yen (USDJPY) has lost about a third of its value since late 2012 when Abe started campaigning for the nation's leadership.

Notable blue chips rose to multiyear highs. Toyota Motor Corp. (TM) rose to an eight-year high. Industrial robot-maker Fanuc Corp. (FANUY) rose to a record high.

How far the rally will go is unclear. From late 1998 to early 2000, Japanese stocks soared as the U.S. dot-com bubble reached Japanese shores, but then crashed when the bubble burst. From 2005 to 2007, the prospect of greater demand from fast-growing economies like China lifted Japanese stocks, especially resources-related ones, until Japan was engulfed by the global financial crisis.

Earlier in February, cash-rich Canon announced it will buy Axis AB , a Swedish network video solutions provider, for around $2.8 billion. Electronics and entertainment giant Sony (SNE) said Wednesday it would spin off its audio and video units to focus on entertainment and image-sensor businesses. Fanuc said Monday it would invest more than $1 billion in new factories and research facilities at home.

Sony shares gained 1.7%. Since late 2012, they have nearly quadrupled. Canon shares have gained 56%.

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