Activist investor Daniel Loeb is proving determination can pay off, even in Japan.

After failing to win major changes from Sony Corp., he picked an even more unlikely target in Fanuc Corp. It was a surprise then on Monday when the secretive industrial-robot maker agreed to return more cash to shareholders, just as Loeb had requested. It is an example of how global investors are starting to get more of Japan Inc.'s $1.9 trillion cash hoard.

Loeb's Fanuc campaign was partly motivated by what he called the "new zeitgeist" in Japan, ushered in by monetary stimulus and promises of corporate reforms from Prime Minister Shinzo Abe. Fanuc's decision to double its dividend payout may be just the start of changes to the country's corporate culture.