At Check Point's current share price, Nacht's exit would bring him $55 million.
Nacht founded Check Point together with serial technology entrepreneur Shlomo Kramer and Gil Shwed, who runs the company in practice.
Nacht owns 26.2 million shares and options, translating into 10.6% of Check Point, based on the last relevant report, from March 2006. Based on Check Point's share price Nacht's shares are worth $570 million.
Of his holding, 3.7 million stock options were exercisable at the start of this year, so his shareholding has probably increased.
Check Point stock options come due in stages, the last being in September 2012.
The company had been generous with stock options to management during its ten years on Nasdaq.
In the last report Shwed held 21 million shares and options, of which 6.2 million options were exercisable at the start of the year. His stake is worth $678 million.
From July, shares in Check Point have rallied strongly, gaining 30%, to $21.80 as of the Nasdaq opening today. The company's market capitalization on Nasdaq is $5 billion.
Check Point stock
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