Reuters reports that PHS operator Willcom has filed for bankruptcy protection with JPY206 billion (USD2.3 billion) in debts. The company has also requested aid from the state-backed Enterprise Turnaround Initiative Corp of Japan (ETIC), the country’s third largest cellco by subscribers Softbank, and Japanese private equity firm Advantage Partners. At the end of 2009 Willcom had 4.3 million subscribers but has been weighed down by heavy debts and has seen a steady decline in its customer base in the wake of fierce competition from NTT DoCoMo, KDDI and Softbank. The company’s current shareholders (Carlyle Group 60%, Kyocera 10%, KDDI 30%) are expected to have their stakes wiped out as the company undergoes a 100% capital reduction. The bankruptcy is believed to be the largest in Japan’s history.