Zynga shares had taken off 5.4% to $4.68 by late afternoon Monday.
King Digital is offering 15.5 million shares at a price between $21 and $24 a share. If it floats at the upper end of that range, its valuation of $7.6 billion would be nearly double Zynga's $4.11 billion market capitalization.
Over fiscal 2013, King Digital pulled in $1.88 billion in sales, 115% higher than Zynga's revenue of $873.3 million. While King Digital posted profits of $568 million, Zynga reported a net loss of $34.07 million.
While hopes are high for King's IPO, investor sentiment towards Zynga has soured. Since it floated at the end of 2011, Zynga shares have plunged 50.6%.
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TheStreet Ratings team rates ZYNGA INC as a Sell with a ratings score of D+. TheStreet Ratings Team has this to say about their recommendation:
"We rate ZYNGA INC (ZNGA) a SELL. This is driven by multiple weaknesses, which we believe should have a greater impact than any strengths, and could make it more difficult for investors to achieve positive results compared to most of the stocks we cover. Among the areas we feel are negative, one of the most important has been weak operating cash flow."