LONDON (Bloomberg) — Prices for insuring corporate clients will probably rise over the next three years as bankruptcies and claims costs increase in the wake of the credit crisis, insurers such as Zurich Financial Services AG and Allianz SE said.

"Rates are going to stabilise and increase modestly over the next three years," Mario Vitale, chief executive officer of the Zurich-based Zurich Financial's global corporate unit, said in a telephone interview last week. "A moderate tightening of the market is my call."

A wave of bankruptcy filings following the financial crisis has helped push up the price of policies protecting company executives from claims related to their jobs, so called directors & officers insurance, in the second quarter, Aon Corp., the world's largest insurance broker, said on September 17. The average price for $1 million in coverage increased four percent in the past year, Aon said.

"There is no doubt that we are at the bottom of the cycle," Axel Theis, head of Munich-based Allianz SE's industrial unit Allianz Global Corporate and Specialty AG, said at an industry conference in Prague on October 7. "We see increases and those increases are needed". Prices won't rise uniformly, he said.

Insurers' underwriting results "have to improve because investment results are declining significantly due to the financial crisis," Allianz's Theis said in a telephone interview last week. "We see considerable rate increases in lines such as aviation, energy and in some parts of the D&O insurance market, for example. The commercial insurance market will harden over the next three years."

Insurance broker Marsh & McLennan Cos. said commercial insurance rates stabilised or rose in Europe in the first half of this year as some insurers reacted to rising claims costs. Price gains "have been limited to the financial institutions", said Dan Glaser, chairman and CEO of Marsh Inc. US. He expects flat reinsurance pricing in January, and rising rates only for "specific lines of business".

"The D&O market is hardening and I think that will continue," said Vitale. In the first six months of this year, Zurich's North American and UK operations have seen "high single digit rate increases". Rates in Europe have also increased, he said.

There were 156 public and major company bankruptcy filings in the US in the first six months of 2009, an increase of 61 percent over the 97 filings in the first half of last year, and almost four times the 41 filings in the first six months of 2007, according to Boston-based New Generation Research Inc.'s bankruptcydata.com.