Cyberinsurance is the fastest-growing insurance product in America, fueled by a slate of recent corporate and government hackings. It’s estimated that the now roughly $3 billion corporate cyberinsurance market will grow to $7.5 billion in premiums by 2020 – compared to flat or falling prices in most other types of insurance.

“Nothing else is growing as quickly as cyber,” said Bob Parisi, cyber product leader for brokerage Marsh, a unit of Marsh & McLennan Cos. “Some of the leading carriers are telling us they are doubling their book every year.”

With rising demand comes rising insurance costs – a 5% to 10% jump in 2017, with larger increases for retailers and health-care companies. For most other types of commercial insurance, prices are expected to decline.

INHERENT RISKS.    Insurers are dealing with a relatively young product, and they don’t have years of actuarial data to rely upon when pricing cyberinsurance plans. That could leave them exposed to risks they don’t fully understand and unexpected costs.

As a result, the job market is red hot for cyberexperts and experienced cyberinsurance underwriters. Marsh joined this year with analytics firm Cyence to help its clients assess their cyberrisk, and broker Aon PLC agreed in October to acquire cybersecurity specialist Stroz Friedberg Inc.

POLICIES.    Most companies with cyberinsurance policies have payout limits of $10 million to $25 million, according to a survey by Aon. Large companies can buy policies with limits above $100 million. While most big U.S. companies have purchased cyberinsurance, coverage remains scant among small businesses and outside the U.S. Cyberinsurance plans are typically narrow and only apply to data breaches, including the cost of notifying customers and complying with state regulations.