Black October combined with the chances that there will be more losses before the end of the year could wind up costing the 350 companies whose stocks are in the S&P 500 more than $300 billion. If employers have to make up these losses by refunding their pension plans, as required under the Pension Protection Act of 2006.

Fifteen trade associations that represent employers that are caught in the pension squeeze have asked Congress “to help companies avoid having to freeze or end pension plans that may be inadequately funded because of the financial crisis,” Reuters reports.

Note the scare tactic being used by the employers that are seeking help from Congress. Help or pensions will be frozen or suspended. That would be a radical move, and General Motors, Ford and Chrysler might very well have to suspend or freeze their pensions due to the financial crisis regardless of whether Congress bails them out.

But most employers would suck up and refund their pension plans rather than get in trouble with their employees, retirees and unions.

For investors, it’s important to know which companies are most at risk. Here are names mentioned this week in the financial press that are varying degrees of risk:

• Lockheed Martin (LMT)
• General Motors (GM)
• Dow Chemical (DOW)
• Unisys (UIS)
• Qwest Communications (Q)
• AT&T (T)
• Consolidated Edison (ED)
• New York Times (NYT)
• Ryder Systems (R)
• Burlington Northern (BNI)

Daily charts for these stocks are here. Click on a chart to see more charts for a given stock.

I doubt that many analysts have factored the pension fund problem into their earnings forecasts for these companies, which makes their forward price earnings ratios and PEG ratios (PE/projected earnings) more suspect than usual.

A big rally before yearend would help reduce the severity of this problem.

I own GM and have covered calls on it.

For educational purposes only. Investigate before you speculate.