Japan's SoftBank improved its net income for the nine months ending in December by 16% year-on-year to 579.4 billion yen ($4.82 billion), despite a decline in third quarter earnings.
Net sales for the nine-month period grew 41% year-on-year to 6.4 trillion yen, with mobile operating income growing to 571.8 billion yen from 521.2 trillion yen.
But for the third quarter, SoftBank reported a 5.9% decline in profit to 191.4 billion yen, with its earnings dragged down by costs associated with its efforts to turn around US operator Sprint Nextel. Sprint's net loss for the quarter more than doubled to $2.38 billion.
SoftBank paid $21.6 billion to acquire a 78% stake in Sprint in June 2013, and has since been trying to turn around the US telco's fortunes. Its latest plan involves taking over up to 1,750 stores operated by bankrupt electronics retailer RadioShack to help increase the operator's retail presence.
SoftBank has maintained its forecast of an operating income of 900 billion yen and net sales of 8 trillion yen for the full financial year. This would mark its first operating profit decline in nine years.
The operator also revealed it has entered a collaboration with IBM to develop a Japanese language version of cognitive computing technology Watson.