Here’s what’s been happening on Wall Street overnight

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There’s a $US60 billion bidding war brewing for Shire, the maker of ADHD medications like Adderall.

Shire has already rejected an offer of that amount from Japan’s Takeda. Shire said in a statement that Takeda’s $US60 billion bid “continues to significantly undervalue the company and Shire’s growth prospects and pipeline.”

Allergan then confirmed it was “in the early stages of considering a possible offer” for Shire. That sent Allergan’s stock price plummeting, falling more than 8%. CNBC then reported Thursday afternoon that Allergan would not make a bid for Shire, with Allergan’s share price rebounding. What a wild ride.

Elsewhere in healthcare news, a leaked video shows Theranos employees playing the video game they created where you shoot at the reporter who exposed the startup’s problems.

In markets news:

Lastly, a trader named Morgan Stanley left Morgan Stanley and now someone is selling his business cards for $US1 million.

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