Following an amended convertible bond agreement, Dish Network Corp. may face US$1.2 addition cost in taking Sprint Nextel Corp. from its rival bidder SoftBank.

SoftBank acquired the seven year bond from Sprint Nextel at the time of its initial bid last October.

The week, the two firms amended the provisions on the debt. This gave the suitor the right to sell the bond back if it loses out to Dish.

Sprint had risen by almost one third after it agreed to the US$20.1 billion from SoftBank. Later the bid was sweetened. Dish was left to pay US$1.2 billion more than what SoftBank paid according to filings. This was based on the 30 day trading average of Sprint's stock.

The added cost is the latest hindrance from Charles Ergen, Dish Network's Chairman. He has spent the last two months battling with SoftBank for the control of US third largest wireless carrier.