I am indian citizen on H1b visa in US. I am planning to visit France in Oct 2014. Can I apply for Schengen visa now about 3/4 months in advance. Are there any restrictions that on early you can apply for Schengen visa.
No you cannot, you can only apply 90 days prior to the start of the visit. This is clearly mentioned on several Schengen Countries' embassies.
For instance, on the German Embassy (VFS Global) for the UK