The rules, which now have 94 provisions from 37 before, come after the China Insurance Regulatory Commission (CIRC) seized Anbang Insurance Group, a firm dogged with allegations of opaque shareholding structures.
Chinese authorities are in the second year of a widening campaign to reduce risks in the financial system, which includes a crackdown on riskier investment products sold by some insurers and probes into whether they are providing covert funding to local governments.
Under the new rules, an insurance company should have clear and reasonable shareholding structure and must reveal the actual controlling entity to the regulator, according to a document handed out in Beijing at a press conference.
He Xiaofeng, head of the commission's working group in control of Anbang and a director at the CIRC, said the regulator faces difficulties authenticating fund sources.
Shareholding structure problems are the root of financial chaos, said He.
The rules, effective from April 10, cover requirements for the qualifications and conduct of shareholders and the management of stock rights.
Also under the new rules, a single shareholder cannot control more than one third of an insurance firm's registered capital, while investors cannot entrust others to hold shareholding in an insurer.
Investors must use their own, legally obtained capital to acquire a stake in an insurer and cannot use a holding company or the transfer of expected returns to bypass restrictions.
Investors are also forbidden from misappropriating insurance funds or repurposing funds for investment.
Money from asset management plans and trust products can be used to acquire listed insurance company stocks, subject to strict conditions.