Average renewal premiums for commercial property/casualty insurance remained fairly flat during fourth quarter compared with a year earlier, the Risk & Insurance Management Society Inc. said in a survey last week.

The survey found that directors and officers liability insurance was the only line tracked that had a material decrease, where premiums dropped 4.6% during the fourth quarter of 2010 compared with a year earlier.

The survey found that large companies with revenues of more than $1 billion experienced larger drops in D&O premiums, 5.1%, than smaller companies, where premiums fell 2.4%.

And David Bradford, editor-in chief of the “RIMS Benchmark Survey” and executive vp of Advisen Ltd., said he does not expect major change in the market this year.

General liability, property and workers compensation policies renewed during the final quarter of last year with “essentially no change” in premiums, RIMS said in a statement about the survey, which was administered by New York-based Advisen. That contrasts with 2009, where general liability and workers comp premiums dropped at least 5% in fourth-quarter renewals compared with a year earlier.

Unlike D&O during 2010, company size was not a meaningful factor in general liability, property and workers comp pricing, New York-based RIMS said.

Some slowing in the rate of decrease was evident in third-quarter renewals. But Mr. Bradford said the fourth-quarter results probably do not signal a hardening market.

“It seems to be a mixed bag depending on who you talk to,” Mr. Bradford said in an interview. “Some underwriters are saying there's a little bit of firming; others say that things are continuing to fall off, but the members were pretty consistent in what they were saying. Overall, there hasn't been much change in the past couple of quarters.”

“I think we're going to see rates rattle around at the bottom of the trough for a while,” Mr. Bradford said. “I don't see them rising materially anytime in 2011. There's way too much capital in the market right now.”

Mr. Bradford said it is a buyers' market, but he added that “could change rather quickly with one or two major catastrophes. But barring any catastrophes, it's pretty much going to be status quo for the year.”

“We have seen more carriers exercising underwriting discipline—walking away from business that does not meet their pricing targets—but it is still a very competitive market,” Robert Cartwright, loss prevention manager of Bridgestone Americas Holding Inc. in Exton, Pa., and a member of the RIMS board of directors, said in the statement.

Advisen analyzes data submitted online from risk managers and other commercial insurance buyers or their brokers. The results are available online or in an annually published book. See www.RIMS.org /benchmark for details.