The past two weeks have seen dozens of third-party headlines speculating about sanofi aventis possibly making a move to acquire Genzyme. Officially, there has been no word with both companies remaining extremely cagey about any of the details. However, Reuters, Bloomberg and a few other sources claim to have squeezed out a few dribbles of information from “people familiar with the situation” and anonymous staff members. So let’s take a look at what may (or may not be) the current situation.

Rumours that sanofi was on the acquisition path actually began at the beginning of July, with speculation that the company was eyeing Allergan, Biogen Idec or Genzyme as potential targets.

By mid July, headlines began to creep out on the internet that sanofi aventis had approached Genzyne about a possible acquisition. Towards the end of the month, more details began to emerge with sources telling Reuters that sanofi was preparing to make a formal offer of up to  $18.7 billion (or about $70 per share) for the biotech.

This week saw Bloomberg speculating that the possible offer of $70 per share wouldn’t be sufficient and that sanofi may have to pay $80 a share (about $21.3 billion). A report from Reuters also agreed that Genzyme would be unlikely to accept an offer under $80 per share. However, Reuters also added that a sanofi aventis shareholder had said that the company would struggle to sell the deal to investors if it offered more than $70 per share.

And the current situation as of 6 August? There’s still no official word from either sanofi or Genzyme, although Reuters appear to have been speaking with Genzyme employees who seem concerned about the impact of a takeover. Sanofi investors, meanwhile, are rumored to be hoping the price for Genzyme won’t exceed more than approximately $19 billion.

Although nobody knows the situation for sure, it’s easy to see why sanofi would be keen to make an acquisition. The company is facing generic threat to Lovenox and, according to Reuters, a fifth of the company’s 2008 drug sales face patent expiries. Genzyme, on the other hand, has a healthy pipeline of profitable drugs for rare diseases.

If sanofi has set its eyes on Genzyme, however, its advances may not go unhindered. The Wall Street Journal points out that Genzyme is one of the few remaining independent biotech firms and other Big Pharma giants facing patent expiries, such as AstraZeneca and GlaxoSmithKline, may also be keeping an eye on the biotech. Indeed, according to some media reports, GlaxoSmithKline has made a casual move towards Genzyme in July.