Oppenheimer & Co. has a Perform rating on shares of Leap Wireless International, Inc. (NASDAQ:

) after it reported earnings last night after the bell. In a note to clients, Oppenheimer writes, "Leap reported mixed 4Q10 results as improving customer adds and ARPU came at the expense of margins. This was a confusing quarter given LEAP closed an acquisition and changed its method of accounting for regulatory fees/telecom taxes which makes comparisons between reported/historical results versus our estimates and consensus meaningless. Notably, though, margin weakness at LEAP was evident and could pressure its shares. PCS shares by default could also be pressured until it reports 4Q results on Thursday. We do believe PCS is further along in its business transformation and its results should continue to outperform LEAP's." Shares of LEAP closed at $13.16 yesterday, down 76 cents.