We present several expected properties of the holomorphic Floer theory of a holomorphic symplectic manifold. In particular, we propose a conjecture relating holomorphic Floer theory of Hitchin integrable systems and Donaldson-Thomas invariants of non-compact Calabi-Yau 3-folds. More generally, we conjecture that the BPS spectrum of a \mathcal{N}=2 4-dimensional quantum field theory can be recovered from the holomorphic Floer theory of the corresponding Seiberg-Witten integrable system.
