Fulfilling the terms of an agreement reached with bondholders in February, Charter Communications submitted a petition for Chapter 11 protection last Friday to the U.S. Bankruptcy Court for the Southern District of New York. The bankruptcy petition would restructure a portion of the debt owed by St. Louis-based Charter, the nation’s fourth largest cable operator with more than 5.5 million subscribers. At the end of last year, Charter listed total debt obligations of $21.7 billion with annual interest costs approaching $2 billion.