Shares in Irish orphan and ADHD drug maker Shire Plc (NASDAQ:SHPG) shot up today on the news that AbbVie (NYSE:ABBV), faced with the oncoming patent loss for Humira and looking to lower its tax rate, made public a rejected $46.5 billion bid today. This was the third bid for Shire from AbbVie, and reportedly management is considering a fourth.

So, why does AbbVie want Shire? In the video below, health care analysts Michael Douglass and David Williamson discuss the proposed deal and what Shire has to offer AbbVie.

David Williamson owns shares of AbbVie. Michael Douglass has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.