Example: pick the stock in your portfolio that you are MOST bullish about. Why isn't every penny you own in that stock?
I don't think it's crazy for officers to sell some of their stock, you've got to convert what you built into cash at some point I suppose. Massive sell-offs are a red flag, but this is only about 6% of his shares, which shouldn't be concerning, especially with Google's sound financial fundamentals.
http://en.wikipedia.org/wiki/Kelly_criterion
Most likely, Eric Schmidt (and most founders/CEOs of big companies) have far more invested in their company than the Kelly Criterion would dictate.
It's also reasonable only if Eric Schmidt thinks there is even the slightest chance that Google's shares will go down at all.
This is almost a certainty. Almost all shares go down in price at some time.
The article cites the idea of diversification - which at face-value seems harmles - , but is this a lack of confidence in the stock? Diversification implies to minimize risk, and that is reasonable only if Eric Schmidt thinks that there is significant risk that Google will underperform market (or at least his expectation of return in a different investment). Unless he has a specific purpose in mind with his extra cash-flow, I would imagine this can only reflect poorly on Google's future expectations.
Here's to hoping that Eric Schmidt only wants to live extravagantly for next couple of years.