In comparison, Sony has put big-budget, popular movies in theaters including "The Amazing Spider Man," ''Zero Dark Thirty" and "Men in Black 3," and has a stronger focus on movies rated PG-13.
The possibility of losing Sony movies was a major risk and would have jeopardized Starz' carriage deals with cable and satellite TV distributors, said Barclays analyst Chris Merwin.
"Had the deal gone to another pay TV network or subscription video on demand provider, it would have put Starz in a very difficult place strategically," he said. Merwin added that it was "very unlikely" that Starz would renew a deal to put its content on Netflix, which expired last year.
He raised his target price on Starz shares to $16 from $15 but kept an "Equal weight" rating.
Janney analyst Tony Wible upgraded Starz to "Neutral" from "Sell" and bumped his estimate on the shares to $16 from $10.50. It remains to be seen how much Starz can offset the higher costs of the deal by raising prices on TV distributors, he noted.
Starz shares rose $1.24, or 7.4 percent, to close at $17.91. Netflix shares fell $3.08, or 1.7 percent, to $177.89. U.S.-traded shares of Sony Corp. shares rose 7 cents to $14.99.