Reports of Pascal Soriot exit fuel mega-merger rumors, but is AZ's oncology pipeline the real driver of the takeover talk?

However it ends, for AstraZeneca (LSE: AZN), the summer of 2017 will not be remembered as a quiet period in the recent history of the Anglo-Swedish pharma company.

There were stories of chief executive Pascal Soriot aiming angry words and threats at Luke Miels, the departing head of the European business, after the latter announced he was joining rivals GlaxoSmithKline (LSE: GSK).

But that scandal seemed barely relevant when a newspaper in Israel claimed this week that Mr Soriot himself was jumping ship, with AZ’s share price plummeting by 4% as rumors first emerged of a shock move to Israeli generics giant Teva Pharmaceutical Industries (NYSE: TEVA). The news also prompted speculation that an AZ and Pfizer (NYSE: PFE) mega-merger, something the Frenchman susscessfully fought to resist in 2013, might be back on the cards.