We introduce filtered cohomologies of differential forms on symplectic
manifolds. They generalize and include the cohomologies
discussed in Papers I and II as a subset. The filtered cohomologies
are finite-dimensional and can be associated with differential
elliptic complexes. Algebraically, we show that the filtered
cohomologies give a two-sided resolution of Lefschetz maps, and
thereby, they are directly related to the kernels and cokernels of
the Lefschetz maps. We also introduce a novel, non-associative
product operation on differential forms for symplectic manifolds.
This product generates an A-infinity algebra structure on forms that
underlies the filtered cohomologies and gives them a ring structure.
As an application, we demonstrate how the ring structure of
the filtered cohomologies can distinguish different symplectic four-manifolds
in the context of a circle times a fibered three-manifold.