On nonfunctional descriptive material

From Ex parte Plastina

We need not give patentable weight to descriptive material absent a new and unobvious functional relationship between the descriptive material and an underlying structure or process. Nonfunctional descriptive material
cannot render nonobvious an invention that would have otherwise been obvious. See In re Ngai, 367 F.3d 1336, 1339, (Fed. Cir. 2004). Cf. In re Gulack, 703 F.2d 1381, 1386, (Fed. Cir. 1983) (“[T]he critical question is whether there exists any new and unobvious functional relationship between the printed matter and the substrate”; when descriptive material is not functionally related to the substrate, the descriptive material will not distinguish the invention from the prior art in terms of patentability); and Cf. In re Lowry, 32 F.3d 1579 (Fed. Cir. 1994):
The PTO did not establish that the ADOs, within the context of the entire claims, lack a new and nonobvious functional relationship with the memory. The ADOs follow a particular sequence that enables more efficient data processing operations on stored data. The ADOs facilitate addition, deletion, and modification of information stored in the memory. In sum, the ADO’s perform a function.
In re Lowry, 32 F.3d at 1583-84. To summarize, if the sole distinction over the prior art is nonfunctional descriptive matter, then the subject matter is obvious in view of the prior art.