With the ever growing rise in popularity of the Marvel Cinematic Universe, once again rumors about Sony's Spiderman being sold or leased back to Marvel are in the works. The matter isn't difficult to understand in basic terms. Marvel naturally created all of their own characters but various studios have wished to involve their intellectual property into their own films. Spiderman is technically owned by Sony who has since produced "The Amazing Spiderman" series, which so far has utterly failed. 

After every failed attempt at making money of their investment in Spiderman, rumors swirl that Sony will attempt to cut their losses. This time, however, the hype appears to be based off of "The Avengers 3," which is still in the negotiation phase with their leading actors. If ever there was a time for Marvel to get Spiderman back for a film or two, this would be it.

This would be quite a difficult task, however, because for Sony there is always the possibly that Spiderman will blow up and become massively successful. Sony has seen firsthand how "The Avengers" series has made well over $1 billion. It's a risky venture either way for the studio.

For starters, limitations would have to be set on how much airtime Spiderman could have in a Marvel film. There is also the issue of how many films he could appear in and what his specific role would be. Naturally, Marvel could always use Spiderman in one film before killing him off in some epic battle. The death of Spiderman could be a major selling point in the series because lets face it, who kills a superhero?

The second issue with the sale or lease is the cost. Marvel will want to underpay and Sony will want to be overly compensated. It's quite possible that if "The Avengers" series would have been a flop then Sony would have no problem handing over Spidey for a couple films.

Studios are in constant competition with one another, and the success of one means failure for another. Marvel famously stopped publishing the "Fantastic Four" comic series when FOX was going to release their "Fantastic Four" film. This kind of industry sabotage is commonplace in the film world. While rumors of Spiderman's future may persist, it is highly unlikely that any agreement will ever be reached.