Roche and Genentech's mating dance — This isn't the first time

Roche has floated an offer to acquire Genentech, a move which has raised a flurry of questions about the sustainability of the big Pharma business model, Genentech’s future independence, and the value of Genentech. It it worth noting, however, that Roche already bought (and sold) Genentech. Using an excerpt from Building Biotechnology to illustrate, Roche pocketed several billion dollars the last time it bought and sold Genentech over a six-week period in 1999:

Source: Building Biotechnology

So, the question must be asked: Despite Roche’s announced plans to include Genentech as an independent research entity, is this transaction simply based on a weak U.S. dollar and an undervalued Genentech? Might they just flip Genentech again?