TheStreet: Starz, the premium cable-TV channel controlled by John Malone, is said to be negotiating with cable operators and could launch an over-the-top video streaming service in partnership with some of those operators by the end of the year. Starz, pay-TV’s second-most popular premium-TV service with 23.5 million subscribers, is looking to join Time Warner’s HBO, the most-watched premium service, and CBS’s Showtime, which both began their own branded video streaming services earlier this year.