Pfizer may have been looking to buy AstraZeneca. Bloomberg reports that the two drugmakers held informal talks a few months ago, according to a report they sourced to London’s Sunday Times. The upshot of the rumors: Pfizer kicked around the number $101 billion.

Both companies have been in a flux of sorts: Pfizer has started readying its financials for a 2017 assessment that would help determine if it will divide into three businesses, while AstraZeneca has been undergoing years of back-to-back churn which have included acquisitions, several rounds of job cuts and naming a CEO.

Jefferies analyst Jeffrey Holford wrote in a Monday analysis that the combination doesn’t seem to make sense for Pfizer  because it would mean riding out a string of patent losses through 2017, exacerbating Pfizer’s “already large patent exposure.” Holford also discounts how helpful AZN’s immuno-oncology portfolio could be for Pfizer, calling AstraZeneca’s category pipeline not ‘well validated enough to justify such a large complex transaction.”

ISI’s Marc Schoenebaum’s Monday research note anticipates that Pfizer shareholders may not like an AstraZeneca scoop, but says such a move would give Pfizer an immuno-oncology foothold. Schoenebaum says Pfizer could not “realistically buy MRK or Roche,” to get into the IO field, which “leaves only AZN if PFE wants a seat at the leader’s table.” Schoenebaum also notes that bringing AZN in-house could give Pfizer another shot at Alzheimer’s, since it would acquire AstraZeneca’s BACE inhibitor, in addition to giving Pfizer access to two other new categories: diabetes and respiratory.