The reported resignation Thursday of the top two executives of Nomura Holdings Inc. caps a remarkable year of upheaval and disgrace at a number of Japan Inc. icons. Does any bigger change follow? Or does corporate Japan's famous inertia and tendency to preserve the status quo prevail?

A few weeks before a spreading insider trading scandal claimed the leaders of Japan's largest brokerage, the long-time chairman of Japan's largest utility -- Tokyo Electric Power Co. -- quit amid widespread outrage over the bungled handling of the Fukushima Daiichi nuclear disaster. Blue-chip camera and medical equipment maker Olympus Corp. cleaned house after admitting to a long-running accounting fraud. One of Japan's largest paper companies, Daio Paper Corp., has been torn by divisions between the founding family and non-family management ever since the founder's grandson was arrested for allegedly instructing subsidiaries to transfer money to his personal bank account to pay for his gambling habit.

Meantime, even some of Japan's non-scandalized leading corporations have been rocked by weak earnings and slumping stock prices. The country's top three consumer electronics companies -- Sony Corp. Panasonic Corp. and Sharp Corp. -- combined to lose $16 billion in fiscal year ended March. All three replaced top executives in recent months, amid pledges of restructuring to improve performance.

The pace of scandal and boardroom turnover is itself remarkable by Japan standards. What's less certain is whether all of that leads to deeper structural reforms. Each corporate problem is, in many ways, unique. But there are also, arguably, some common threads: a broad corporate and regulatory system that has had relatively lax checks and balances, an establishment that has tended to sweep uncomfortable questions under the rug in order to preserve the status quo.

Critics say that, even amid such problems, the resilience of the old system has been remarkable. Tepco's old executives are gone and the company has been effectively nationalized. But a broader restructuring of the electricity industry is still far from certain. Olympus seems likely to preserve its independence, albeit with a capital tie-up with a partner. Even as investigators ramped up their insider trading probe, suspiciously heavy trading has continued in advance of market-moving announcements. Amid the heavy losses, the large electronics companies seem unwilling -- or unable -- to shed one of their biggest burdens, their once-dominant, now-struggling, television units.