Riot on Tuesday said it submitted an unsolicited proposal to buy Bitfarms for $2.30 per share in a deal that would create the world's largest bitcoin miner.
Bitfarms said the offer was unsatisfactory and that it had received additional unsolicited expressions of interest from other parties.
A committee of the board considering the approach "determined it significantly undervalues the company and its growth prospects," the Toronto-based firm said Wednesday. "In order to advance discussions with Riot in a meaningful manner, the committee requested customary confidentiality and non-solicitation protections to which Riot did not respond."
Bitfarms also said it hired investment bank Moelis to serve as a financial adviser.
BITF shares rose nearly 5% to $2.31 during early trading on Wednesday.
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