According to the Wall Street Journal Nortel, the now-defunct telecommunication equipment manufacturer, has been the victim of corporate cyber-espionnage for a decade or so. Plenty of time for the intruders to secure access to R&D work, business plans and other valuable information. The intrusion appears to have been spotted a first time in 2004 but its sophistication level was so high that it continued five more years.
The story does not end there: after its bankruptcy, Nortel was split into pieces and sold (hardware included) to several companies among which Avaya and Ericsson (whose heads of IT security must be running extra-securty checks on their Chinese corporate computer networks these days).
What reads like a spy novel is probably more frequent than one suspects. The risk of cyber-theft is considered high enough that officials from US government agencies use ‘loaner devices’ as a standard operating procedure (wiped cleaned before departure for China and upon return).