What will Roche end up paying for Genentech?

The first lawsuits are flying but Roche’s experienced dealmakers are unlikely to put more cash on the table just yet.

While it seems clear $89 a share won’t do it – the market has already pushed Genentech stock to $95 and some analysts are talking well over $100 – the Basel-based drugs giant can afford to bide its time. With 56 percent of the biotech company already in his pocket, Chairman Franz Humer is ready to play a long game.

Genentech, which says Roche’s bid for the remaining 44 percent is “unsolicited and unexpected”, has formed a special committee of its three independent directors to assess the proposal. They will be engaging outside advisors, suggesting a lengthy process ahead.

At the end of the day, most analysts believe a deal looks inevitable and Roche will end up sweetening its current $43.7 billion offer.

The question is, by how much?