Advantest (ATE) has sweetened its bid for chipmaker Verigy (VRGY), proposing to buy all of its outstanding shares for $15 each. The company had made an earlier offer of $12.15 a share.

The Verigy board said it would not make any recommendation at this time with respect to the revised offer, but would continue engaging in discussions with Advantest, including regulatory considerations.

Despit the revised bid, the Verigy board continued, as of Thursday, to recommend the LTX-Credence (LTXC) merger agreement to its shareholders. Based in Cupertino, California, Verigy agreed to buy rival LTX-Credence for $438 million.

Verigy had previously said the proposal from Advantest, a Tokyo-based manufacturer of semiconductor test systems, was not superior to its proposal with LTX.

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