As a result, Lockheed Martin will have to account for the deal under different accounting rules, called purchase accounting.

If the accounting board changed the rules on purchase accounting, those companies would have had a favorable accounting method to use, he said.

This latest problem is related to improper purchase accounting, Ahold said in a news release, without elaborating.

Those charges must be reported in the only alternative method, known as purchase accounting.

Now it will decide what changes need to be made in the other form of merger accounting, called purchase accounting.

If the companies were forced to use purchase accounting, analysts estimate that a $50 billion premium would be written off over 20 years.

And if those divestitures amounted to more than 25 percent of the companies' assets, securities regulators could then force them to use purchase accounting.

Companies would then be left to use purchase accounting, which is already the only available method in most of the rest of the world.

The alternative method is known as purchase accounting.

The other method of merger accounting is purchase accounting, which Wells is using.