The U.S. Securities and Exchange Commission plans to hold a panel discussion on controversial accounting rules at 9:30 a.m. EST Friday.

The participants in the discussion, on mark-to-market accounting rules, will include Kevin Spataro of the Allstate Corp., Northbrook, Ill., and Mark Thresher of Nationwide Financial Services Inc., Columbus, Ohio.

Some observers blame mark-to-market accounting rules for aggravating the effects of the economic turmoil on financial services companies; other accuse mark-to-market accounting rule critics of wanting to “break the thermometer because they don’t like the temperature.”