AbbVie Inc. announced yesterday that its Board of Directors will meet by October 20 to reconsider its recommendation to shareholders to approve a $51.5 billion acquisition of Shire Plc that would move its legal address to the UK.  AbbVie noted that the board will consider the impact of the proposed changes to the tax regulations announced September 22 by the Treasury Department, including the impact to the fundamental financial benefits of the transaction.  Shire released a statement today encouraging AbbVie to proceed with the offer on the agreed terms.