Class actions are continuing to drive up directors’ and officers’ insurance premiums amid heightened scrutiny of listed companies, according to Aon.

At least 15 securities class actions, including competing claims, have been filed against listed companies since January last year and a further five or more are being considered, according to the group’s first-quarter market insights report.

Aon says class actions are typically accompanied by investigations by the Australian Securities and Investments Commission, which is gaining funding to step up its regulatory activities.

“The roles of directors and others vested with stewardship responsibility continue to become more onerous as their roles become subject to increasingly active oversight by regulatory authorities, shareholders and those acting on their behalf, and by special interest and advocacy groups.”

Companies on the ASX 200 experienced a median 122% increase in primary premiums in the second half of last year, following an 89% gain in the first six months, based on Aon data.

The report says pressure on premiums will continue for listed businesses, and companies with smaller market capitalisations may see larger increases.

The evolving environment and the lack of predictability around many class actions is hindering efforts to accurately model premium requirements.

“This is demonstrated by the volatility in premiums offered between insurers and is especially evident in layers of insurance purchased between the primary layer and a limit of liability of $70 million.”

Most insureds should anticipate a minimum deductible of $1-10 million for any securities entity claim, the report says.

Non-listed organisations are also experiencing modest upward pressure on premiums based on their risk profiles and business sectors. Those operating in the retail, construction, energy and health sectors are becoming more subject to particularly rigorous review by insurers.

Aon says climate change is another risk area receiving increased focus from regulators and advocacy groups.