 Shares of Viasat Inc. VSAT, 2.98 sank 3.0 in premarket trading Monday, after the communications network company announced an agreement to buy mobile satellite communications services company Inmarsat in a deal valued at 7.3 billion, including 3.4 billion in debt. Under terms of the deal, Viasat will pay 850 million in cash and 46.36 million shares of Viasat common stock, which is valued at 3.11 billion based on Fridays closing price of 67.00. 