DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114 was filed in this application after appeal to the Patent Trial and Appeal Board, but prior to a decision on the appeal. Since this application is eligible for continued examination under 37 CFR 1.114 and the fee set forth in 37 CFR 1.17(e) has been timely paid, the appeal has been withdrawn pursuant to 37 CFR 1.114 and prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant’s submissions filed on March 2, 2026 and May 5, 2026 have been entered.
Response to Amendment
Applicant’s amendment has been entered. Claims 1-3 and 21-32 are pending. Claims 4-20 are canceled. Changing all instances of “megalpascals” to “megapascals” has overcome the objections to claims for minor informalities regarding “megalpascals”; however, the previously set forth objection for the slurry solution remains.
Response to Declaration under 37 CFR § 1.132
The declaration under 37 CFR 1.132 filed March 2, 2026 is insufficient to overcome the rejection of claims 1-3 and 21-32 based upon 35 USC 112(a) as set forth in the last Office action because: the record, including declaration evidence does not demonstrate that the written description, as filed, is adequate to support the claim(s).
Paragraph 6 of the declaration by Heeman Choe (the declaration) purports that paragraph [23] and Figs. 6A and 7 of the specification as filed support the limitation “a first curve comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals” recited in independent claim 1 and independent claim 31. Paragraph [23] of the present disclosure discusses structural, non-porous magnesium. Paragraph [23] does not discuss the properties of magnesium foam. Paragraph [23] is pasted below:
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Paragraph 6 of the declaration indicates that Figs. 6A and 7 show that a single example of the inventive magnesium alloy foam with a porosity of 52% increasing stress up to 123 MPa at an engineering strain between 25 and 27%. The disclosure, not the declaration indicates that Figs. 6A and 7 show results for a single composition. Paragraph [41] of the present disclosure states that Fig. 6A shows a compressive stress strain curve (a “compressive” stress-strain curve is more specific than the general stress strain curve recited in claim 1) for samples 1 and 2, and paragraphs [11-21] and [28-33] indicate that all samples, including the samples in Figs. 6 And 7 are formed from AE42 alloy. AE42 is a magnesium alloy comprising aluminum and rare earth metals, as described in paragraph [07] of the present disclosure. Paragraph [41] also provides what appears to be the only numerical values from the curves in indicating that a single sample experienced a yield point at about 50 megapascals and that strain hardening occurred from yield to about 120 megapascals. Fig. 6A shows that even if two foams are produced from AE42 alloy, the resulting foams may not exhibit the same compressive stress-strain behavior. Claim 1 claims a composition of matter comprising a three dimensionally connected magnesium or magnesium alloy foam [of unspecified porosity] of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg- Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these [significantly broader than AE42], wherein some first curve [not necessarily a compressive stress-strain curve of the composition] comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals. Paragraph 6 of the declaration only shows that the disclosure, as filed reported a compressive strain-strain curve for a single composition, at a specific porosity has some point within the bounds of claim 1. The declaration does not sufficiently explain how this single example may be extrapolated to reasonably convey support for breadth of the claimed structure meeting this new first curve limitation. Paragraph 6 of the declaration closes with the sentence “[t]hese outstanding mechanical properties originate from its unique, well-constructed 3D foam structure that someone not having skill in the art cannot properly appreciate”. This sentence underscores why the limited disclosure of the mechanical behavior of a single example is not sufficient to support a newly claimed attribution of that limited mechanical behavior to a broad range of structures.
Paragraphs 7-10 and 12 of the declaration appear to change only the claim number from paragraph 6 of the declaration without providing further evidence. Paragraph 11 of the declaration restates claim limitations. As claims 7-12 do not provide further evidence as to how the disclosure as filed supports first curve claim limitations paragraphs 7-12 of the declaration, do not add sufficient evidence to the record to show that first curve limitations are supported by the disclosure as filed.
Paragraph 13 of the declaration 13 points to paragraphs [13], [37], and Fig. 3 as evidence of support for the limitation “a second curve comprises a first point of about 8 to 10 microns and a log differential intrusion of about 1-1.3 milliliters per gram” recited in claim 26. This showing largely is insufficient because this point is not on Fig. 3. Note that Fig. 3 shows a pore size of 8-10 at a log differential intrusion closer to 0.3. The x-axis pore size decreases in moving from left to right. Paragraphs [13] and [37] of the specification describe Fig. 3 and do not sufficiently explain why a figure which does not contain the claimed point would support a claim to a curve comprising that point. Even if the second curve limitations were adjusted to claim a point on the curve shown in Fig. 3, the declaration does not provide evidence that the curve of the pore size distribution would apply to more than the one example with a single composition and porosity.
MPEP 716.09 provides a further discussion on declaration evidence under 37 CFR 1.132 to support sufficiency of the disclosure. MPEP 716.09 describes evidence of sufficiency with respect to both the written description and enablement requirements of 35 USC 112(a). MPEP 716.09 is blunt with respect to the written description requirement, noting: “[a]ffidavits or declarations presented to show that the disclosure of an application is sufficient to one skilled in the art are not acceptable to establish facts which the specification itself should recite. In re Buchner, 929 F.2d 660, 18 USPQ2d 1331 (Fed. Cir. 1991) (Expert described how he would construct elements necessary to the claimed invention whose construction was not described in the application or the prior art; this was not sufficient to demonstrate that such construction was well-known to those of ordinary skill in the art.); In re Smyth, 189 F.2d 982, 90 USPQ 106 (CCPA 1951)”; “[a]ffidavits or declarations purporting to explain the disclosure or to interpret the disclosure of a pending application are usually not considered. In re Oppenauer, 143 F.2d 974, 62 USPQ 297 (CCPA 1944)”; “But see Glaser v. Strickland, 220 USPQ 446 (Bd. Pat. Int. 1983) which reexamines the rationale on which In re Oppenauer was based in light of the Federal Rules of Evidence. The Board stated as a general proposition "Opinion testimony which merely purports to state that a claim or count, is ‘disclosed’ in an application involved in an interference . . . should not be given any weight. Opinion testimony which purports to state that a particular feature or limitation of a claim or count is disclosed in an application involved in an interference and which explains the underlying factual basis for the opinion may be helpful and can be admitted. The weight to which the latter testimony may be entitled must be evaluated strictly on a case-by-case basis."”.
The declaration under 37 CFR 1.132 filed March 2, 2026 is insufficient to overcome the rejection of claims 1-3 and 21-32 based upon 35 U.S.C. 103 as being unpatentable over Guo (CN107326208A) as set forth in the last Office action because: the evidence is insufficient to show that that the prior art products do not necessarily possess the characteristics of the claimed product.
MPEP 2112(V) and MPEP 2112.01 set forth that once the office establishes a sound basis for believing that the claimed and prior art composition inherently have the same structure, burden shifts to applicant to provide evidence that prior art structure does not necessarily or inherently meet the claimed property. Paragraph 14 of the declaration copies only the portion of the office action mailed September 2, 2026 which cites MPEP 2112 without considering the features which Guo discloses which informed the sound basis for believing that the composition disclosed by Guo would meet the claimed structure. Such features disclosed by Guo to support the sound basis for believing that Guo meets the claimed first curve limitations include the mechanical properties disclosed by Guo [0006], [0079], [0088], [0097], the sintering conditions disclosed by Guo [0032], and the overall foam structure disclosed by Guo [0002], [0070], [0088], [0090], [0097].
Declarant’s evidence in paragraphs 14 and 15 appear to be an assertion that the prior office action is incorrect because the instructions in MPEP 2112 and 2112.01 only apply to bulk materials. Declarant’s interpretation is not sufficient evidence to show that the composition disclosed by Guo fails to meet the claimed first curve limitations.
Declarant concludes paragraph 15 of the declaration by qualitatively indicating that differences in pore structure can result in differences in compressive strength. Declarant does not support this qualitative assertion with numerical values or other evidence which shows that the structure disclosed by Guo would not necessarily or inherently meet the claimed first curve limitations. In fact, Figs. 6A, 7, 8, and 10 appear to be the only stress-strain curves for magnesium alloy foams of record, and these curves all appear to meet the first curve limitation of claim 1, in view of the present disclosure. See the below statement of claim interpretation. A qualitative assertion that compressive strength depends on pore structure combined with an argument that the teachings of MPEP 2112 and 2112.01 do not apply to porous compositions is insufficient as evidence that the prior art structure does not inherently or necessarily meet the claimed structure, particularly when weighed against the evidence of record for which all magnesium alloy compressive stress-strain curves of record meet the claimed structure. Guo discloses a porous magnesium alloy foam [0002], [0070], [0090].
In view of the foregoing, when all of the evidence is considered, the totality of the rebuttal evidence of nonobviousness fails to outweigh the evidence of obviousness.
Claim Objections
Claims 30 and 32 are objected to because of the following informalities:
In claims 30 and 32, please change “freeze casting the camphene-based magnesium or magnesium alloy powder slurry solution” to “freeze casting the slurry solution” for consistency within the claims.
Appropriate correction is required.
Claim Interpretation
Each of claims 1-3, 22-28, and 30-31 contains numerical quantities modified by the word “about”. The specification does not provide specific numerical bounds as to how “about” is intended to be interpreted; therefore, in order to definitively establish a range of specific activity covered by limitations modified by “about” the terms modified by “about” in claims 1-3, 22-28, and 30-31 will be interpreted as encompassing ±10% of the recited numerical value. An interpretation is necessary to establish clear, objective bounds on the claim.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-3 and 21-32 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Independent claim 1 claims “a first curve comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals”; claim 22 claims “the first curve comprises a second point of engineering strain of about 4 to 6 percent and engineering stress of about 64-69 megapascals”; claim 23 claims “the first curve comprises a third point of engineering strain of about 39 to 41 percent and engineering stress of about 147-152 megapascals”; claim 24 claims “the first curve comprises a second point of engineering strain of about 19 to 21 percent and engineering stress of about 123-125 megapascals”; claim 25 claims “the first curve comprises a third point of engineering strain of about 32 to 34 percent and engineering stress of about 126-128 megapascals”, and claim 31 claims “a first curve comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals, a second point of engineering strain of about 19 to 21 percent and engineering stress of about 123-125 megapascals, and a third point of engineering strain of about 32 to 34 percent and engineering stress of about 126-128 megapascals”.
In remarks filed June 2, 2025, applicant states, “[t]he new and amended claims are fully supported by the specification. For example, see figures 3, 6A, 7, and 10 and accompanying description. No new matter has been added.” Fig. 3 does not show a stress-strain curve. Fig. 6A is a compressive stress-strain curve for two samples formed from AE42 Mg alloy powder, as directly shown in Fig. 6A and described in paragraphs [16] and [41]. Fig. 7 appears to show a stress-strain curve of one of the samples from Fig. 6A with additional acoustic emission analysis as described in paragraphs [17] and [42]. Only one curve of Fig. 10 (1006) shows some stress vs. strain for one sample, and this curve appears to again be one of the examples shown in Fig. 6A. The only numerical values of stress for these curves are provided in paragraph [41] which indicates that the single sample experienced a yield point at about 50 megapascals and that strain hardening occurred from yield to about 120 megapascals. Paragraph [41] does not disclose values of the strain at these yield points leaving only the curves of at most two different samples of the same alloy composition, shown in the figures, as support for the claimed stress-strain properties.
The disclosure of at most two examples of a common alloy composition, even when considered in view of the broader disclosure as filed, does not reasonably lead one of ordinary skill in the art to the claimed composition exhibiting the claimed stress-strain behavior over the claimed composition of matter comprising a three dimensionally connected magnesium or magnesium alloy foam of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg- Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these with the possible exception of the limited foam formed from AE42 Mg alloy powder. The disclosure as filed is not written to sufficiently and reasonably convey to one skilled in the relevant art that the inventor or a joint inventor had possession of composition of a matter comprising a three dimensionally connected magnesium or magnesium alloy foam foams of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg-Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these, wherein some curve shows some stress-strain behavior as recited in claims 1, 22-25, and 31.
Claim 26 claims “a second curve comprises a first point of about 8 to 10 microns and a log differential intrusion of about 1-1.3 milliliters per gram”. Claims 27 and 31 each claim “a majority of pore sizes is about 8-10 microns”. The only portion of the specification as filed which appears to show pore size limitations which claims 26-27 and 31 appear intended to recite is Fig. 3. As indicated in paragraph [08], Fig. 3 actually shows a median pore distribution at about 13 microns. In describing Fig. 3, paragraph [37] give 12.6 microns as a more precise value for the median shown in Fig. 3. Note that values of pore size on the x-axis of Fig. 3 decrease in moving from left to right. Not only are the claimed pore size values recited in claims 26-27 and 31 absent from the disclosure as filed, but the sole example distribution presented and described fails to meet the claimed pore size limitations. Further, even if the claimed pore sizes were limited to that shown in Fig. 3, the single example shown in Fig. 3 and described in the specification as filed would be sufficient to support the pore size limitations as claimed.
Claims 2-3 and 21-30 are rejected under 35 USC 112(a) because they depend on claim 1. Claim 32 is rejected under 35 USC 112(a) because it depends on claim 32.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-3 and 21-32 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claims 1, 22-25, and 31, independent claim 1 in its entirety claims “A composition of matter comprising a three dimensionally connected magnesium or magnesium alloy foam foams of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg-Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these, wherein a first curve comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals.” In claiming a composition and the existence of a curve without indicating what specific property that curve measures, it is not clear what structure is encompassed by the claimed curve. While applicant appears to intend to recite that a certain amount of stress is required to deform the claimed composition by a given strain, and the specification suggests a compressive deformation mechanism, as worded, claim 1 does not link the claimed curve to a physical property of the claimed composition. The claimed first curve, as claimed, is unrelated to the composition. Applicant is encouraged to claim what the curve actually is, in relation to the composition instead of merely claiming a composition and the separate existence of some curve. For example, this limitation would be more clearly set forth by specifying the claimed point as a point on a stress strain curve when the composition in subjected to a specific amount of a specific type (compressive, tensile, shear, torsional, etc.) of strain. The stress strain curve relations recited in claims 22-25 and 31 are similarly uncertain because it is not clear what structure of the claimed composition is limited by recitations of such curves.
Claim 3 as worded claims “The composition of claim 1 wherein a magnesium or magnesium alloy green-body foam has a sintering process comprising (i) burning of chemical additives at about 300 degrees Celsius to about 450 degrees Celsius for about 3 hours to about 5 hours and (ii) sintering of magnesium or magnesium alloy green-body foam at 500 degrees Celsius to 650 degrees Celsius for about 3 hours to about 10 hours in argon atmosphere.” Claim 1 introduces a composition comprising a magnesium or magnesium alloy foam. It is not clear how the processing steps of claim 3 limit the claimed composition. If applicant intends claim 3 to claim that the composition according claim 1 is produced by subjecting a magnesium or magnesium alloy green-body foam to a sintering process, applicant should claim the composition according claim 1, wherein the composition according to claim 1 is produced by subjecting a magnesium or magnesium alloy green-body foam to a sintering process, otherwise it is not clear how the claimed sintering process, as worded, limits the composition. Note how claims 29, 30 and 32 are worded.
Regarding claim 26, claim 26 claims “a second curve comprises a first point of about 8 to 10 microns and a log differential intrusion of about 1-1.3 milliliters per gram”. It is not clear from the claims as worded how this limitation limits the structure of the claimed composition(s). Notably several different length scales of the claimed composition including particle diameter, pore size, or microstructure phase diameter can have measurements on the order of the claimed length scale. Applicant is encouraged to reflect on the structure of the composition intended to be encompassed by the recited limitations and claim the structure depicted by the curve, such as pore size distribution, instead of the curve itself.
Claims 27 and 31 claim a majority of pore sizes is about 8-10 microns. It is not clear in view of the specification, what proportion of pores a composition must have in order for the majority of pores to be in the range of 8-10 microns. The portion of the disclosure as filed on which applicant appears to rely to support the pore size limitations of claims 27 and 31 appears to be Fig. 3 for which the median pore size is 12.6 microns, and a median value of a distribution is only the majority when the number of items within that median bucket exceeds the combined number of all other values. Median does not equate to majority.
Claims 2-3 and 21-30 are rejected under 35 USC 112(b) because they depend on claim 1. Claim 21 is rejected under 35 USC 112(b) because claim 21 depends on claim 3. Claim 32 is rejected under 35 USC 112(b) because it depends on claim 32.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1-3 and 21-32 is/are rejected under 35 U.S.C. 103 as being unpatentable over Guo (CN107326208A). Guo is cited in prior office action(s). References to Guo are directed to the examiner-supplied English language translation which accompanied the office action mailed December 2, 2024.
Regarding claim 1, Guo discloses a magnesium or magnesium alloy foam [0002]. composition of matter comprising a three dimensionally connected [0070] magnesium or magnesium alloy foams [0002], wherein an example magnesium alloy is an alloy of Mg-Al [0090].
Guo discloses that the produced foam has a good strength [0079], [0088], [0097] and notes that magnesium has a higher strength than aluminum [0006], and Guo discloses a porosity of between 30% and 65% [0022], but Guo is silent on values the foam would attain when plotted on a compressive stress-strain curve, as claim 1 appears intended to recite. Compressive stress-strain behavior is a material property that is inseparable from the chemical composition of the material. See MPEP2112.01(II). When the claimed and prior art products are substantially identical in structure or composition, or are produced by substantially identical processes, a prima facie case of obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer See MPEP2112(I). Guo discloses that producing the foam comprises a multi-step sintering process comprising heating to a temperature of 300-350°C, then heating at 580-600°C in a low-pressure (vacuum) argon atmosphere [0032]. The present disclosure indicates that producing the magnesium or magnesium alloy foam comprises a sintering at 300 degrees Celsius to about 450 degrees Celsius then sintering of magnesium or magnesium alloy green-body foam at 500 degrees Celsius to 650 degrees Celsius in argon atmosphere (paragraph [30], claim 3), and the present disclosure indicates that the overall deformation behavior of the magnesium foam of the present invention appeared quite similar to that of the bulk magnesium alloy [61]. All examples of the magnesium foam of the present disclosure appear to meet the stress-strain properties recited in claim 1 (Fig. 6A). Considering Guo’s disclosure of a desirable strength in the disclosed foam [0006], [0079], [0088], [0097], the porosity of the foam disclosed by Guo [0022], and the sintering conditions disclosed by Guo [0032], when compared with the limited instructions that the present disclosure provides to one of skill in the art to obtain the claimed stress-strain properties, Guo establishes a sound basis for believing that the range of foam structures disclosed and suggested by Guo [0002], [0022], [0070], [0088], [0090], [0097] encompasses some structure for which a plotting of a compressive stress-strain curve would attain some point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 MPa.
Regarding claim 3, Guo discloses that producing the foam comprises a multi-step sintering process comprising heating to a temperature of 300-350°C, then heating at 580-600°C in a low-pressure (vacuum) argon atmosphere [0032]. Guo teaches that controlling the sintering conditions allows the magnesium constituents to bond without cracking [0037] and that the overall process of manufacture controls the foam porosity [0039]. Present claim 3 appears intended to be written in a product-by-process format for which the determination of patentability is limited by the structure implied by the recited steps and not by the manipulation of the process steps. See MPEP 2113(I). Considering the process conditions disclosed by Guo [0032], [0037], [0039], Guo’s disclosure of a magnesium or magnesium alloy foam [0002], [0090] and the pore structure disclosed by Guo [0070], which Guo discloses is controlled by process conditions [0039], the structure of the foam disclosed by Guo [0002], [0070], [0088], [0090], [0097], would meet that implied by the steps recited by the product-by-process limitations of claim 3. Further, the sintering temperatures in an atmosphere comprising argon disclosed by Guo [0032], overlap sintering temperatures recited in apparent product-by-process limitations of claim 3. Such overlapping conditions would have resulted in a range of foam structures which overlap or approach the range of foam structures implied by the product-by-process limitations recited in claim 3. When claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists, and prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. See MPEP 2144.05(I).
Regarding claims 2 and 26-27, Guo discloses examples wherein a porosity is 50% [0088], and 65% [0097]. Guo discloses an overall porosity of between 30% and 65% [0022] which overlaps a range of about 45 percent to about 85 percent. When claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. See MPEP 2144.05(I). Guo discloses an overall method for preparing porosity-controlled foamed magnesium or magnesium alloy wherein the pore size is uniform and the pores are regularly arranged in three-dimensional space [0070]. Guo is silent on whether the pores are open or closed, and Guo is silent on pore size distribution. Open porosity and pore size distribution are material properties that are inseparable from the chemical composition and processing of the material. See MPEP2112.01(II). When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer See MPEP2112(I). Considering the porosity disclosed by Guo [0022] overlaps the ranges recited in claim 2, the sintering parameters disclosed by Guo which control porosity [0032], [0037], [0039], as applied to claim 3 above, and the uniform pore structure which Guo discloses [0070], Guo establishes a sound basis for believing that the range of structures disclosed by Guo [0002], [0022], [0070] produced by the processes disclosed by Guo [0024-39] would yield a range of structures which at least comprise some degree of open porosity, thereby meeting the open porosity limitation recited in present claim 2, and encompass some structures wherein a median pore size is about 8 to 10 microns and encompasses structures wherein a median pore size is about 13 microns which would encompass the limitations of claims 26 and 27 as the limitations appear intended to be interpreted.
Regarding claim 21, claim 21 depends on claim 3 which appears to be intended to recite limitations in a product-by-process format. Guo discloses that during mixing feed powders are dispersed with ethanol, dried, and then bound to each other during shaping and sintering [0024-29], [0054-56]. The determination of patentability is limited by the structure implied by the recited steps and not by the manipulation of the process steps. See MPEP 2113(I). Considering Guo discloses a structure which of dispersed powder bound together [0024-29], [0054-56], and considering the present disclosure removes binder and dispersant from an intermediate product to produce the product composition [30], the product foam disclosed by Guo applied above would meet the structure implied by burning of binder and dispersant.
Regarding claims 22-25, Guo discloses that the produced foam has a good strength [0079], [0088], [0097] and notes that magnesium has a higher strength than aluminum [0006], but Guo is silent on values the foam would attain when plotted on a compressive stress-strain curve, as claims 22-25 appear intended to recite. Compressive stress-strain behavior is a material property that is inseparable from the chemical composition of the material. See MPEP2112.01(II). When the claimed and prior art products are substantially identical in structure or composition, or are produced by substantially identical processes, a prima facie case of obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer See MPEP2112(I). Guo discloses that producing the foam comprises a multi-step sintering process comprising heating to a temperature of 300-350°C, then heating at 580-600°C in a low-pressure (vacuum) argon atmosphere [0032]. The present disclosure indicates that producing the magnesium or magnesium alloy foam comprises a sintering at 300 degrees Celsius to about 450 degrees Celsius then sintering of magnesium or magnesium alloy green-body foam at 500 degrees Celsius to 650 degrees Celsius in argon atmosphere (paragraph [30], claim 3), and the present disclosure indicates that the overall deformation behavior of the magnesium foam of the present invention appeared quite similar to that of the bulk magnesium alloy [61]. Considering Guo’s disclosure of a desirable strength in the disclosed foam [0006], [0079], [0088], [0097], and the sintering conditions disclosed by Guo [0032], when compared with the instructions that the present disclosure provides to one of skill in the art to obtain the claimed stress-strain properties, Guo establishes a sound basis for believing that the range of foam structures disclosed and suggested by Guo [0002], [0070], [0088], [0090], [0097] encompasses some structure for which a plotting of a compressive stress-strain curve would attain some point of engineering strain of about 4 to 6 percent and engineering stress of about 64-69 MPa, thereby meeting the additional limitations recited in claim 22; some point of engineering strain of about 39 to 41 percent and engineering stress of about 147-152 MPa, thereby meeting the additional limitations recited in claim 23; some point of engineering strain of about 19 to 21 percent and engineering stress of about 123-125 MPa, thereby meeting the additional limitations recited in claim 24, and some point of engineering strain of about 32 to 34 percent and engineering stress of about 126-128 MPa, thereby meeting the additional limitations recited in claim 25.
Regarding claim 28, Guo discloses that the foam comprises a foam comprises a three-dimensional pore structure [0070] with uniformly distributed pores [0039], [0070]. Guo discloses that the sizes of the particles which are removed to form the pores are 25-250 µm [0046], [0073], [0082], [0091]. Considering the filler material which Guo removes to form the pores has a diameter of 25-250 µm [0046], [0073], [0082], [0091], and 25-250 µm lies comfortably within a from about 1 micron to about 300 microns, the diameter of the pores disclosed by Guo formed by removing the pore-forming material would have a size at some point in a range from about 1 micron to about 300 microns.
Regarding claim 29, Guo discloses taking deliberate action to avoid oxidizing feed magnesium during production [0056]. Guo discloses that the ultimately formed composition is a foam with a uniform three-dimensional pore structure [0070], and Guo discloses a porosity of between 30% and 65% [0022]. Guo discloses producing the material by sintering [0032]. The limitations of claim 29 are recited in product-by-process format for which patentability is limited by the structure implied by the recited steps and not by the manipulation of the process steps. See MPEP 2113(I). The present disclosure indicates that the steps recited in claim 29 result in the structure of a stable suspension without an oxide layer [27]. Considering the porosity of the magnesium foam disclosed by Guo [0022], sintering conditions disclosed by Guo [0032], and providing feed materials to avoid oxidation disclosed by Guo [0056], the structure of the composition disclosed by Guo, applied above would meet structure implied by performing the steps set forth in claim 29.
Regarding claim 30, Guo discloses that the composition is made by a method comprising: mixing magnesium or magnesium alloy powder having a particle size 25 to 150 μm in a solution [0024-29], [0046], [0054-56] 25-150 µm encompasses from about 36 microns to 45 microns. When claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. See MPEP 2144.05(I). Guo discloses taking deliberate action to avoid feed magnesium oxidation during production [0056]. Guo discloses that the ultimately formed composition is a foam with a uniform three-dimensional pore structure [0070], and Guo discloses a porosity of between 30% and 65% [0022]. Guo discloses producing the material by sintering [0032]. The limitations of claim 30 are recited in product-by-process format for which patentability is limited by the structure implied by the recited steps and not by the manipulation of the process steps. See MPEP 2113(I). The present disclosure indicates that the steps recited in claim 30 result in the structure of a stable suspension without an oxide layer [27]. Considering the feed particle size disclosed by Guo [0046], the porosity of the magnesium foam disclosed by Guo [0022], sintering conditions disclosed by Guo [0032], and providing feed materials to avoid oxidation disclosed by Guo [0056], the structure of the composition disclosed by Guo, applied above would meet structure implied by performing the steps set forth in claim 30.
Regarding claim 31, Guo discloses a magnesium or magnesium alloy foam [0002]. composition of matter comprising a three dimensionally connected [0070] magnesium or magnesium alloy foams [0002], wherein an example magnesium alloy is an alloy of Mg-Al [0090].
Guo discloses that the produced foam has a good strength [0079], [0088], [0097] and notes that magnesium has a higher strength than aluminum [0006], and Guo discloses a porosity of between 30% and 65% [0022], but Guo is silent on values the foam would attain when plotted on a compressive stress-strain curve, as claim 31 appears intended to recite. Compressive stress-strain behavior is a material property that is inseparable from the chemical composition of the material. See MPEP2112.01(II). When the claimed and prior art products are substantially identical in structure or composition, or are produced by substantially identical processes, a prima facie case of obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer See MPEP2112(I). Guo discloses that producing the foam comprises a multi-step sintering process comprising heating to a temperature of 300-350°C, then heating at 580-600°C in a low-pressure (vacuum) argon atmosphere [0032]. The present disclosure indicates that producing the magnesium or magnesium alloy foam comprises a sintering at 300 degrees Celsius to about 450 degrees Celsius then sintering of magnesium or magnesium alloy green-body foam at 500 degrees Celsius to 650 degrees Celsius in argon atmosphere (paragraph [30], claim 3), and the present disclosure indicates that the overall deformation behavior of the magnesium foam of the present invention appeared quite similar to that of the bulk magnesium alloy [61]. Considering Guo’s disclosure of a desirable strength in the disclosed foam [0006], [0079], [0088], [0097], and the sintering conditions disclosed by Guo [0032], when compared with the instructions that the present disclosure provides to one of skill in the art to obtain the claimed stress-strain properties, Guo establishes a sound basis for believing that the range of foam structures disclosed and suggested by Guo [0002], [0070], [0088], [0090], [0097] encompasses some structure for which a plotting of a compressive stress-strain curve would attain some point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 MPa; some point of engineering strain of about 19 to 21 percent and engineering stress of about 123-125 MPa, and some point of engineering strain of about 32 to 34 percent and engineering stress of about 126-128 MPa.
Guo discloses examples wherein a porosity is 50% [0088], and 65% [0097]. Guo discloses an overall porosity of between 30% and 65% [0022] which overlaps a range of about 45 percent to about 85 percent of the present invention (claim 2). Guo discloses an overall method for preparing porosity-controlled foamed magnesium or magnesium alloy wherein the pore size is uniform and the pores are regularly arranged in three-dimensional space [0070]. Guo is silent on pore size distribution, including on the median pore size, which claim 31 appears intended to claim. Pore size distribution is a material property that is inseparable from the chemical composition and processing of the material. See MPEP2112.01(II). When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer See MPEP2112(I). Considering the porosity disclosed by Guo [0022] overlaps the ranges of the foam of the present invention (claim 2), the sintering parameters disclosed by Guo which control porosity [0032], [0037], [0039], (see the application of Guo to claim 3 above), the porosity disclosed by Guo [0022], and the uniform pore structure which Guo discloses [0070], Guo establishes a sound basis for believing that the range of structures disclosed by Guo [0002], [0022], [0070] produced by the processes disclosed by Guo [0024-39] would yield a range of structures which encompass some structures wherein a median pore size is about 8 to 10 microns and encompasses structures wherein a median pore size is about 13 microns which would encompass the pore size limitation of claim 31 as the limitation appear intended to be interpreted.
Regarding claim 32, Guo discloses taking deliberate action to avoid feed magnesium oxidation during production [0056]. Guo discloses that the ultimately formed composition is a foam with a uniform three-dimensional pore structure [0070], and Guo discloses a porosity of between 30% and 65% [0022]. Guo discloses producing the material by sintering [0032]. The limitations of claim 32 are recited in product-by-process format for which patentability is limited by the structure implied by the recited steps and not by the manipulation of the process steps. See MPEP 2113(I). The present disclosure indicates that the steps recited in claim 32 result in the structure of a stable suspension without an oxide layer [27]. Considering the porosity of the magnesium foam disclosed by Guo [0022], sintering conditions disclosed by Guo [0032], and providing feed materials to avoid oxidation disclosed by Guo [0056], the structure of the composition disclosed by Guo, applied above would meet structure implied by performing the steps set forth in claim 32.
Response to Arguments
Applicant's arguments filed March 2, 2026 and May 5, 2026 have been fully considered but they are not persuasive.
Applicant argues that the claim amendment addresses the informalities which prompted the claim objections. While the amendment corrects the “megalpascals” issues, amendment did not correct inconsistencies which prompted objections for consistency in referring to the slurry in claims 30 and 32.
In both remarks filed March 2, 2026 and May 5, 2026, applicant argues, supported by the declaration by Dr. Heeman Choe filed under 37 CFR 1.132 that the claimed parameters for engineering strain and engineering stress are explicitly substantiated by the experimental data provided in the specification. This is not persuasive because the only experimental data showing stress-strain behavior meeting some point on some stress-strain curve, is an example compressive stress-strain curve of a AE42 alloy foam with 52% porosity. This one example is not sufficient to reasonably support the scope of the presently claimed composition of matter comprising a three dimensionally connected magnesium or magnesium alloy foam of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg- Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these, which is not limited to AE42 alloy, wherein a first curve, which is not claimed as a curve that plots a property of the particularly claimed magnesium or magnesium alloy foam, comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals, wherein the claim does not specify the mode of strain. At best both the disclosure as filed and the declaration by Dr. Choe provide support for one, single example which would meet the curve limitation if the curve limitation were better specified. A single example is not sufficient to reasonably support the breadth of the claims which contain first curve limitations added June 2, 2025, which is after the filing date of the application.
Paragraph [41] of the specification as filed indicates that the compressive stress in one example increases up to 120 MPa until strain hardening occurs. Paragraph [41] does not indicate that a three dimensionally connected magnesium or magnesium alloy foam of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg- Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these, which is not limited to AE42 alloy, wherein a first curve, which may or may not have anything to do with the stress-strain behavior of the particularly claimed composition, comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals. The claimed invention is more than the one, limited example. See MPEP 2163.05(II) for a further discussion on how adding a limitation that was not supported could raise issues under 35 USC 112(a).
Applicant’s remarks filed March 2, 2026 and May 5, 2026 suggest that the remarks and/or amendments are intended to further traverse the rejections under 35 USC 112(b). As the remarks do not indicate how the claimed first curve limits the structure of the claimed composition of matter, the rejections regarding the first and second curve are maintained. Please claim what the first and second curve are in relation to the structure of the claimed composition of matter. As worded claim 1 claims a composition of matter comprising a foam wherein a first curve comprises a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals. Claim 1 does not claim that the first curve is a compressive stress-strain curve for either the composition of matter or for the foam.
Note further, this is the third office action which rejects claim 3 under 35 USC 112(b) because it is not clear if the claim is intended as a product-by-process claim. As worded claim 3 claims the composition of claim 1 wherein a green body is subjected to processing steps. If claim 3 is intended to claim a composition produced by the claimed processing steps, this should be more clearly set forth in the claim.
Regarding rejections under 35 USC 103 over Guo (CN107326208A), applicant argues that the presently claimed invention yields unexpected results over the prior art. This argument is not persuasive because applicant does not support the argument with evidence that the presently claimed composition yields unexpected results to a statistical and practical significance commensurate in scope over that of the prior art, as described in MPEP 716.02 for evaluating evidence of unexpected results.
Applicant appears to compare the result of the present invention with that of fully dense magnesium. The Introductory paragraph of MPEP 716.02 sets forth that the results should be unexpected over that of the prior art. MPEP 716.02(e) explicitly states “[a]n affidavit or declaration under 37 CFR 1.132 must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness”. Without a comparison of the presently claimed structure with that disclosed by Guo, there is not sufficient evidence to evaluate whether the presently claimed structure yields unexpected results over that of Guo.
Further, the results must be commensurate in scope with the claim (MPEP 716.02(d)). All results of record are limited to AE42 alloy foam, which is a very small sliver of the scope encompassed by the claimed “composition of matter comprising a three dimensionally connected magnesium or magnesium alloy foam of at least one of Mg-Al, Mg-Zn, Mg-Al, Mg- Mn, Mg-Si, Mg-Cu, Mg-Zr, or Mg-rare earth elements, or any combination of these”.
Applicant’s arguments cannot take the place of evidence were evidence is necessary (MPEP 716.01(c)(II) and 2145(I)).
Applicant’s argument that the statement that “[c]ompressive stress-strain behavior is a material property that is inseparable from the chemical composition of the material” is an “Incorrect Scientific Premise” is not persuasive because the chemical composition was only one of several aspects of Guo inseparable from the resulting mechanical properties on which prior office actions relied to establish a sound basis for believing that the structure disclosed by Guo would meet some point on a stress-strain curve as recited in present claim 1. Notably prior office actions relied on mechanical properties [0006], [0079], [0088], [0097], and sintering conditions [0032] disclosed by Guo. An argument that the rejection distilled the rationale for establishing a sound basis for believing that Guo meets the claimed first curve limitation entirely to the composition not only ignores, but contradicts the explicit record which establishes the sound basis for believing with mechanical and processing conditions disclosed by Guo. The present office action further supports the sound basis for believing that the structure disclosed by Guo would meet the claimed stress-strain curve with the porosity disclosed by Guo [0022].
Both MPEP 2112 and 2112.01 indicate that once a sound basis for believing that the prior art structure would necessarily or inherently meet a claimed feature, burden shifts to applicant to provide evidence that the prior art structure would not necessarily or inherently meet the claimed structure. A characterization of a statement in an office action, regardless of whether or not applicant agrees with the statement, does not amount to evidence of failure to meet a limitation.
Applicant argues that the claimed structure is different from the structure disclosed by Guo. Applicant supports this argument with the qualitative statement from the declaration “For metal foams or porous metals, the compressive stress-strain behavior can differ depending on many factors, such as porosity, pore size, and pore- connecting structure. Furthermore, metal foams with the same composition and porosity can show different stress-strain behaviors depending on their pore structure design (e.g., random versus directional), the degree of particle or strut connection, distribution of pore size, and other differences”. This argument is not persuasive because the argument does not actually show values of a compressive stress-strain curve for different porosities, pore sizes, and pore- connecting structures. The features which Guo discloses including the composition [0002], [0070], [0090], porosity [0022], favorable mechanical properties [0006], [0079], [0088], [0097], and sintering conditions [0032] are more than sufficient to establish a sound basis for believing that the structure disclosed by Guo would meet the claimed first curve limitation. Applicant’s qualitative assertions, are not sufficient to show that Guo would not necessarily or inherently meet the claimed first curve limitations. Applicant has yet to point to a magnesium or magnesium alloy foam wherein a first point of engineering strain of about 25 to 27 percent and engineering stress of about 118-123 megapascals (note the above claim interpretation for quantities modified by “about”).
Regarding rejections under 35 USC 103, applicant appears to argue only the “first curve” limitations which appear in both independent claim 1 and independent claim 31.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SEAN P O'KEEFE whose telephone number is (571)272-7647. The examiner can normally be reached MR 8:00-6:30.
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/SEAN P. O'KEEFE/ Examiner, Art Unit 1738
/SALLY A MERKLING/ SPE, Art Unit 1738
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