From their high perches, each failed to see a major shift in technology and never really recovered. Just because companies in the SV150 survived one or two waves of changes doesn't mean they're safe. It's vanquished all major competition when it comes to selling networking equipment to large businesses for their internal corporate networks. Now it's trying to sell to phone companies and Internet service providers. Fortunately, the valley is one big innovation machine.
Nobody can predict where things are going to go.
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