I don't agree with your statements on either institutional or insider selling.
The data that I see for the last 6 months indicates that institutions are buying, not selling. The number that I see indicates a net purchase of 36m shares. I was surprised about the positive number in light of the drop from $29. There is an extra 100,000,000 shares short over that period.
3 Intel inside sellers and no buyers for INTC is not that strange. If you want to see insider selling look at QCOM.