Did Rambus Use Patent Ambush Tactics?

The European Commission is joining various US courts in examining the legal rights and wrongs of Rambus.  Apparently the EC is taking issue with Rambus allegedly not properly disclosing all of its patents to potential customers who were interested in acquiring licenses for other Rambus technology.

By not telling customers that Rambus held patents in relevant technology that was essentially required to properly utilize technology they licensed to others, Rambus was setting themselves up for a future law suit against their own clients and licensees.

Whether or not there were outstanding reasons for this practice is not, at this time, clear.
“Rambus has nine weeks to reply to the charges, after which it will have the right to be heard. If it fails to satisfy regulators, it could be fined up to 10 pct of its annual worldwide turnover.”
Do you think Rambus made an honest mistake, or was this perhaps a method to keep unruly customers from making too much of a fuss in the media?
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