In determining novelty of the subject-matter of claims, the examiner must have regard to the guidance given in F‑IV, 4.5 to F-IV, 4.21. Particularly for claims directed to a physical entity, non-distinctive characteristics of a particular intended use are to be disregarded (see F‑IV, 4.13.1). For example, a claim to a substance X for use as a catalyst would not be considered to be novel over the same substance known as a dye, unless the use referred to implies a particular form of the substance (e.g. the presence of certain additives) which distinguishes it from the known form of the substance. That is to say, characteristics not explicitly stated, but implied by the particular use, are to be taken into account (see the example of a "mold for molten steel" in F‑IV, 4.13.1). For claims to a first medical use, see G‑II, 4.2.
A known compound is not rendered novel merely because it is available with a different degree of purity if the purity can be achieved by conventional means (see T 360/07).