Shares in Softbank fell more than eight percent on Tuesday after a US satellite-television provider trumped the Japanese mobile operator's bid to acquire Sprint Nextel.
Softbank shares were down 8.11 percent at 4,305 yen in Tokyo trade after DISH Network on Monday launched an unsolicited $25.5 billion bid against Softbank's October offer to acquire 70 percent of Sprint for $20 billion.
DISH said it was offering to buy Sprint, the third-largest US wireless carrier, for $17.3 billion in cash and $8.2 billion in stock, trying to derail Softbank's attempt to acquire the No. 3 US wireless carrier.
Softbank's attempt to get itself a chunk of the US market looks like it is going to get a lot more expensive, Hideyuki Ishiguro, senior strategist at investment strategy at Okasan Securities, told Dow Jones Newswires.
"It's difficult to imagine that Softbank will not raise its Sprint bid, since the only growth is overseas," he said.
"Under the new Bank of Japan policy, capital is cheaper than ever, and banks are willing to lend," he said, referring to massive monetary easing steps the Japanese central bank is taking.
"A bidding war might be likely, but Softbank is equipped to win."
The purchase by Softbank, if it goes through, would mark the biggest overseas acquisition by a Japanese firm.
Softbank declined to comment on the latest development in the planned deal, which still needs a green light from US regulators looking at possible national security conflicts.
DISH Network chairman Charlie Ergen said in a statement that its proposal "clearly presents Sprint shareholders with a superior alternative to the pending Softbank proposal".
"Sprint shareholders will benefit from a higher price with more cash while also creating the opportunity to participate more meaningfully in a combined DISH/Sprint with a significantly-enhanced strategic position and substantial synergies that are not attainable through the pending Softbank proposal."
In an email to AFP, Sprint said the unsolicited DISH bid would be evaluated by its board of directors.
In New York DISH Network shares dropped 2.3 percent while Sprint jumped 13.5 percent.