President Xi Jinping's top economic adviser commissioned a study earlier this year to see how China could avoid the fate of Japan's epic bust in the 1990s and decades of stagnation that followed.

The report covered a wide range of topics, from the Plaza Accord on currency to a real estate bubble to the demographics that made Japan the oldest population in Asia, according to a person familiar with the matter who has seen the report. While details are scarce, the person revealed one key recommendation that policymakers have since implemented: the need to curtail a global buying spree by some of the nation's biggest private companies.

Communist Party leaders discussed Japan's experience in a Politburo meeting on April 26, according to the person, who asked not to be identified as the discussions are private. State media came alive afterward, with reports trumpeting Xi's warning that financial stability is crucial in economic growth.