The bidding for the Dutch bank ABN Amro is the biggest takeover battle in years. And now the momentum is back with its preferred buyer, Barclays of Britain.

A legal adviser to the Supreme Court of the Netherlands has found that ABN Amro did not need to put its sale of LaSalle Bank of Chicago to a vote of shareholders. In March, Bank of America agreed to pay $21 billion for LaSalle, a deal that is key to blocking a $95.5 billion rival offer for ABN Amro from a consortium led by the Royal Bank of Scotland.

In April, however, a Dutch court blocked the sale of LaSalle, putting the deal with Bank of America in limbo and stymieing Barclays’ attempts to close its $86 billion acquisition of ABN Amro.

In Tuesday’s opinion, the Dutch advocate general, Levinus Timmerman, did not express a position on whether the board of ABN Amro acted unlawfully with respect to its shareholders by selling LaSalle but concluded only that under Dutch company law, such a transaction does not require approval from a general meeting of shareholders.

While the court need not heed the opinion of the advocate general, it has done so in about eight of the past 10 cases.

If the court allows the sale, the Royal Bank of Scotland group could still counter with a bid for ABN Amro that excludes LaSalle, the Financial Times notes.