Euronet, a Kansas-based maker of automated teller machines, said it made an all-stock offer for MoneyGram valued at $20 a share on Dec. 4. That represents a 43% premium to the stock's price that day and a 34% premium over the shares' close on Wednesday.
Shares of MoneyGram were surging $4.60, or 31%, to $19.50 in premarket trading Thursday.
MoneyGram rebuffed the merger proposal and declined to discuss the deal with Euronet, according to a letter to MoneyGram's board made public Thursday by Euronet.
Euronet said in the letter that a merger would combine two complementary businesses and expand the geographic network of both companies.
The deal calls for a fixed exchange ratio of 0.6179 shares of Euronet for each MoneyGram share; this would give MoneyGram shareholders a 46% stake in the combined company.
Euronet is seeking to enter a confidentiality agreement to conduct due diligence and said it would be prepared to increase its offer if the review warrants it.