This deal has reportedly been in the works for at least the last few weeks. According to Reuters, FCA already rejected a roughly $2.7-billion offer in June. Marchionne apparently wants at least the equivalent of $3.3 billion for the company.
Publicly, FCA isn't talking, though. Company spokesperson Gualberto Ranieri told Reuters and reiterated to Autoblog simply that Magneti Marelli wasn't for sale. However, a move to get rid of the parts company has been discussed in the past. In 2013, the business was rumored to be part of a purported arrangement to sell Alfa Romeo to Audi.
While there's no final decision yet, according to Reuters, if the Magneti Marelli sale does move forward the decision would likely come sometime after the Ferrari IPO. The company would likely be split up among the various divisions. "Everyone will take a fair share of it," one of the anonymous sources to Reuters.