At $4.8 trn, Japan Inc has more cash than most nations' GDP sitting idle

While companies see the money as a buffer against hard times, it has long riled investors, who say executives should invest it for growth or return it to shareholders

In banks across Japan sits a pile of money that’s bigger than most countries’ gross domestic product -- the cash reserves of the nation’s companies. For some it’s a testament to their strength, but to many it’s a wasted opportunity.

Firms listed in Japan held 506.4 trillion yen ($4.8 trillion) in cash as of their latest filings, the highest level on record, according to data compiled by Bloomberg. It’s more than tripled since March 2013, months after Prime Minister Shinzo Abe returned to power vowing to stamp out cash-hoarding.

While companies see the money as a buffer against hard times, it has