In the emerging technology of additive manufacturing, obtaining patent coverage can present challenges. Sometimes the inventive concept relates to a particular working material in combination with aspects of the 3D printing apparatus. In such cases, many applicants have been blocked by over-zealous examiner relying MPEP 2115 which boldly claims that:

Claim analysis is highly fact-dependent. A claim is only limited by positively recited elements. Thus, “[i]nclusion of the material or article worked upon by a structure being claimed does not impart patentability to the claims.” In re Otto, 312 F.2d 937, 136 USPQ 458, 459 (CCPA 1963); see also In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935).

The MPEP thus provides examiners the ability to simply ignore "included" material or articles that are worked upon by a claimed structure. The "include" here is important, as the way the sentence is set forth in the MPEP makes it seem like that refers to claimed material or articles worked upon - otherwise why bother as examiners generally do not concern themselves with unclaimed elements.

However, the PTAB recently issued a decision which seems to create a significant exception to MPEP 2115. The case is a Siemens application (14/071,774) related to additive manufacturing that claimed a particular bed of powered metal in an apparatus. Claim 1 is set forth below:

1. An additive manufacturing apparatus comprising:
     a chamber comprising a side wall and a bottom wall but not a top wall, and an opening comprising a perimeter defined at least in part by the side wall, the opening permitting
unrestricted fluid communication between an interior of the chamber and atmospheric gases;

     a fluidized bed of powdered material including powdered metal material and powdered flux material in the chamber;

     a scanning system that is disposed in the atmospheric gases and that emits an energy beam that selectively scans portions of a surface of the bed of powdered material to heat and melt the powdered material which then solidifies to form metal deposits; and,

     one or more controllers to control relative movement between the energy beam and the metal deposits according to a predetermined shape of a component.

The examiner ignored the cited limitation as merely article being worked on because it should not be accorded patentable weight, citing MPEP 2115. The Examiner alleged that the ordinary artisan would understand that, as the apparatus is operated, the powdered material is worked upon and eventually removed in the form of a solidified article, and a new supply of powdered material is introduced into the chamber to continue operation. The Examiner further based the rejection on the reasoning that the powdered materials are not only consumed in the process of using the apparatus, but also make up the additively manufactured article produced by the apparatus. Siemens appealed to the PTAB and overcame the rejection. The PTAB went through the cases law, rather than the MPEP's characterization, and explained the interrelation to the similar theory of intended use, noting that these cases are "highly fact dependent":

In Otto, the relevant claims were directed to, as an article of manufacture, a core member for hair curlers comprising an elastically resilient foam body carrying in its pores a hair waving lotion in non-liquid form. Otto, 312 F.2d at 937-938. The Otto court noted that the recitation involving the hair being wound directly on the foam body was irrelevant to
the claims' patentability as "inclusion of the material or article worked upon by a structure being claimed does not impart patentability to the claims." Id. at 940. The court further noted that no means for attaching hair to the body was recited in the claims. Id. at 941. Thus, in Otto, the material being worked upon was hair which was not positively recited as an element of the claims, but was instead directed to the intended use of the article of manufacture.

In Young, the claims were directed to machines for making concrete beams, wherein one of the claims, claim 6, recited "concrete reinforced structures." Young, 75 F.2d at 996. The Examiner in Young rejected claim 6 on the ground that it improperly included, as an element, the material being worked upon, which rejection the Board approved. Id. at 998. The Young court further stated that "its inclusion may not lend patentability" to the
claim which was otherwise not allowable. Id.

In Casey, the claims were directed to a taping machine, but failed to positively recite the tape. Casey, 370 F.2d at 577. Casey argued that the claims fundamentally differed from the prior art in the intended use of the devices; Casey's was a tape dispenser while the prior art was a perforating device. Id. at 942. The Casey court held that this difference related to the
method of intended use of Casey's device and, therefore, did not distinguish the device over the prior art. Id. The Casey decision further discusses the proper weight to be accorded preambles as positive structural limitations, finding in this case that the preamble did not recite more than the intended use. Id. at 943.

Neither Otto nor Casey actually positively recited the feature identified in these decisions as the material worked upon, i.e., the hair in Otto and the tape in Casey. Instead, Otto and Casey argued features of the method of using the claimed article or machine which were directed to the intended uses thereof. Further, while Young appears to have attempted to
positively recite the final product made by the claimed apparatus, the court therein acknowledged that this was material being worked upon which could not lend patentability to a claim to the apparatus for making that product.

Unlike Otto, Young, and Casey, the claims here positively recite, as a structural element of the claim, a fluidized bed of powdered material, wherein the powdered material includes powdered metal material and powdered flux material. Further, the fluidized bed of powdered material is not the final product. Although the Examiner is correct that a small amount of the powdered material of the fluidized bed is consumed in the process of using the apparatus for forming or repairing a component, as Appellants disclose, the fluidized bed actively functions as part of the apparatus (Reply Br. 9). Appellants disclose that "by fluidizing a bed of powdered material that includes both metal powdered materials and flux powdered materials[,] substrates can be formed continuously without incrementally forming layers to build up a substrate and without the need of introduction of expensive inert gases" (Spec. 5:22-26). In addition, Appellants disclose that adequately fluidizing the bed so that a sufficient amount of powdered material will settle for processing depends on a number of inter-related parameters including, among others, the size and density of the powdered materials (id. at 6:7-11). Thus, the powdered materials are necessary parameters of the fluidized bed, which itself is a structural element of the apparatus.

We recognize that whether a claim recites material worked upon, like the analysis of preambles discussed in the Otto and Casey decisions, requires a fact-based case by case analysis that, in some cases, present close questions. However, here the apparatus claim positively recites a structural element, the fluidized bed of powdered material, and there is sufficient disclosure to support that this fluidized bed and the particular powdered
materials therein are structural limitations of the apparatus, rather than merely material worked upon by the apparatus. Accordingly, the Examiner's determination that "powdered metal material and powdered flux material" is merely directed to material being worked on by the apparatus and is not entitled to patentable weight is harmful error. Because the
Examiner's obviousness rejection relies on this erroneous determination, the Examiner's conclusion of obviousness lacks sufficient rational underpinning. ...

So, if an examiner ignores non-final products worked upon in your apparatus claim under MPEP 2115, follow the approach the PTAB lays out here to show why the examiner must not ignore these elements.