Schmidt, even after selling significant amount of his shares, will play, if not central, but a good part in functioning of Google according to Needham and Co analyst Kerry Rice. 

"My speculation is that Eric's relationship with Google is evolving," said Rice. "I would assume that as he decides he wants to diversify away from Google - both his career and financially - he's got ideas of what he would like to do with some of his funds."

Schmidt is credited for the growth of Google into top search engine of the world in his 10 years stint as Google’s CEO. In April 2011 he handed over the reign to Larry Page.

"As Google moves to maybe more tactical battles, as opposed to the strategic battles it's been waging with the government, once those are concluded, maybe his role can be lessened," said Rice.

Google said that Schmidt entered into the stock trading plan in November.

Schmidt was ranked 138 on the Forbes list of global billionaires with a net worth of $6.9 billion in March 2012.

Given Schmidt's changed role at the company and the amount of his wealth tied up in Google's stock, it was not unreasonable for him to diversify his holdings, said Wedbush Securities analyst Dix.

"As good as Google stock is, it isn't as good as cash if you actually want to buy something," he added.

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