According to ComicBookMovie.com on Dec. 23, rumors have been going around about Sony Pictures killing off Spider-Man in "The Amazing Spider-Man 3". This could be merely speculative of fans, but sources indicate that Andrew Garfield has only signed on for parts two and three.
That being said, since it's been announced by Sony Pictures that there would be a "Venom" movie as well as a film about the Sinister Six villains, it could stand to reason that these roles would fall into the "Spider-Man 4" film. A lot of fans have been wondering how a film without Spider-Man would even be produced.
Comic books tend to have their own story arcs or events, but by compiling the information that's been presented so far, one could think an entire movie with villains and lacking the webslinger may be plausible. It could be a sub plot that may predicate to future Spider-Man franchises.
However, with Oscorp seemingly an underlying corporation that might be spawning villain technology, there could be a considerable chain reaction of events that could launch the Sony Pictures franchise into a successful competition with its Disney competitor.