In the latest twist to Playtech's offer for troubled trading shop Plus500 (LON:PLUS), its largest shareholder with over 25%, said it would oppose the bid.
The Playtech offer, unveiled on Monday, valued the Aim-quoted company at 400p a share, 8.1% above Plus500's 370p closing price last Friday but well below the 750p it was trading at the middle of last month.
Shareholder Odey Asset Management says the bid is opportunistic and exploits current regulatory issues.
The Hedge fund giant told a regulatory statement: "In our view 400p materially undervalues Plus500 and we do not intend to vote in favour of the cash acquisition of Plus500 at this price.
"Even considering the current regulatory issues and near term risks, we believe the intrinsic value of the business on a longer term view is materially higher than 400p."
It added: " We welcome Plus500 management's approach to Playtech's proposed cash acquisition, which allows other potential bidders the opportunity to appraise Plus500 with the same information as Playtech, and which allows management to cease its commitment to Playtech's proposed cash acquisition should another bidder present a higher offer."
PLUS shares gained 0.54% to 372p on Thursday.
But shares in the Israeli group tumbled when it revealed it suspended some of its UK client accounts to carry out money laundering checks.
The issue has yet to be resolved.