On Festo and "Means"

In patenting, Festo is a doctrine of equivalence: if a patent claims a, b, c - this can sometimes also include c (broad claiming). But since the actual Festo, if one starts off broad and narrow, then one cannot claim broader (doctrine of equivalence) again.

Means + Function is no-no in patent claims. The combination refers to a too general component expressed functionally (which begs for a method claim language: a module for cooling), as opposed to structurally (what it is, i.e., a cooling module, and not only what it does). See the Patent Writing:Claims tag for similar topics.