In a conference call with journalists on Sept. 14, the chief executives of Bayer and Monsanto expressed confidence that their planned $66 billion merger will face few antitrust obstacles as there are no significant overlaps in their portfolios. Asked to name areas where questions might be raised, Bayer CEO Werner Baumann declined comment, saying he didn’t want to give ideas to the 30 authorities that will be probing the merger. Monsanto CEO Hugh Grant said, however, that from a regulatory perspective, “I think it’s a very clean deal.”

Sidestepping the question of overlap, Grant said Monsanto’s strengths are in seeds and in biotech, while Bayer’s are along the chemistry chain. Analysts have identified possible overlaps in cotton and canola seeds as well as in herbicides.

Along with competition authorities, the two agribusiness giants said they plan to specifically ask the US Committee on Foreign Investment, CIFUS to scrutinize the deal to assure they have covered all regulatory angles. The committee reviews possible implications of deals involving a foreign partner with an eye to national security concerns. CIFUS recently greenlighted the takeover of Syngenta – which has a considerable US presence – without much fanfare.

The US Federal Trade Commission and the European Commission are likely to have far more questions from a regulatory perspective. The EU executive last week said it had suspended its deadline for an extended probe into the proposed merger of Dow and DuPont because the companies had nott submitted important information.

As the Commission is also expected to require some time to thoroughly examine the Syngenta-ChemChina merger plans, many observers believe Bayer’s confidence of closing the deal next year may be misplaced.

Some commentators have noted that many of the German company’s biggest shareholders oppose the tie-up with Monsanto as it clearly shifts corporate weight away from pharmaceuticals – in their view a more lucrative field. This could negatively affect the company’s share price.

As it struggles to transparency in vetting the multiple mergers it must pass judgment on, the Commission will undoubtedly come under pressure from environmental advocates opposed to genetic manipulation, many of whom believe Bayer’s acquisition of Monsanto could open the floodgates for GMO crops in the EU. In the US, Chuck Grassley, chairman of the Senate judiciary committee, has called a hearing for later this month on all the megadeals.

With a lot of money riding on a successful conclusion of the all-cash transaction– Bayer has now raised its pledged break-up fee to $2 billion – executives on the conference call, which also included Liam Condon, head of Bayer CropScience, and Bayer CFO Johannes Dietsch, sidestepped more detailed questions by stressing the perspective driving innovation in agriculture through synergies and financial strength.  Based on combined 2015 figures, the new entity will have an R&D budget of $2.5 billion.

Whether jobs could be at stake – especially in Germany, where Bayer has a much larger workforce compared with Monsanto – how managerial positions would be filled or even what name the new company would be called were issues the players asserted had not yet been hammered out.