[chmike]

Why waiting so long ? There should be a prescription on this type of claims. This technology is used in a very visible way for years now. So they could not ignore it and thus implicitly permitted to use it.

If they didn't knew they had these patents, how could the other company know ?

This type of pattent 'mines' will have the consequence to scare to death companies. Foreign companies will stay away of US just to avoid the risk to step on such mine. And US companies may move their business in countries with much less risks (i.e. europe, Asia).