By Greg Roumeliotis, Nadia Damouni and Liana B. Baker NEW YORK (Reuters) – Neustar Inc, a company which helps North American telecommunication carriers route calls and text messages, is considering a potential sale amid interest from private equity firms, according to people familiar with the matter. No formal sale process is currently underway but Neustar is working with investment bank JPMorgan Chase & Co as it reviews possible options following a more than 40 percent drop in its share price year-to-date, the people said this week. Neustar shares were trading up 10 percent on the news at $31.5 in afternoon trading in New York. Much of Neustar’s woes stem from a major government contract it stands to lose to Ericsson AB subsidiary Telcordia Technologies.