Satellite company Inmarsat (FRA:IV4) saw shares plunge over 10 percent on Friday morning, after the group rejected a takeover from the US’ biggest satellite firm.

According to Inmarsat, the $3.2 billion bid made by EchoStar “very significantly undervalued Inmarsat and its standalone prospects”.

EchoStar already holds a small stake in Inmarsat, and said it will continue to pursue its interest in the group.

“EchoStar continues, however, to seek engagement with the board of Inmarsat on a constructive basis, with a view to agreeing the terms of a recommended offer,” the company said.

EchoStar’s offer valued the group at 532p a share, with many believing Inmarsat’s board will want a much higher offer in order to win over shareholders.

London-based Inmarsat employs more than 1,500 people and has 13 satellites in orbit. It has provided technology used by the British armed forces, although its largest single customer is the US military.

Shares in Inmarsat are currently trading down 7.74 percent at 5.48EUR (1000GMT).