A coalition that includes Netflix, HBO and cable-industry titans is stepping up efforts to crack down on password sharing, discussing new measures to close a loophole that could be costing companies billions of dollars in lost revenue each year, Bloomberg reported Friday. From the report: Programmers and cable-TV distributors are considering an array of tactics to cut off people who borrow credentials from friends and relatives to access programming without paying for it. The possible measures include requiring customers to change their passwords periodically or texting codes to subscribers’ phones that they would need to enter to keep watching, according to people familiar with the matter. Some TV executives want to create rules governing which devices can be used to access a cable-TV subscription outside the home. While someone logging in from a phone or tablet would be fine, someone using a Roku device at a second location could be considered a likely freeloader, one person said. If none of those tactics work, pay-TV subscribers could someday be required to sign into their accounts using their thumbprints.