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 .
Claim Status
An amendment, filed 12/8/2025, is acknowledged. Claim 17 is amended. Claims 15-29 are currently pending, claims 15-16, 19, 21-26, and 29 are withdrawn.
Claim Rejections - 35 USC § 112
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 17-18, 20, and 27-28 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.
Claim 17 recites the limitation "the sintered metal particles" in lines 3. There is insufficient antecedent basis for this limitation in the claim.
Additionally, claim 17 is drawn to “A porous sintered metal body” “having a porosity from 50 percent to 80 percent” but also claims “wherein the sintered metal particles have a relative apparent density in a range from 5 percent to 35 percent of a theoretical density of the particles.” One of ordinary skill in the art would recognize that the metal particles, once sintered, no longer constitute individual particles but form a solidified metal body. Therefore, it is unclear if the claimed relative apparent density relates to metal particles prior to sintering, or is a representation of the relative density of the metal body, a measure strongly correlated with its porosity. In the latter interpretation the claimed relative apparent density may be interpreted to conflict with the claimed porosity, as metal particles having a relative apparent density below 20% could result in a sintered metal body with more than 80% porosity. Claims 18, 20, and 27-28 are indefinite based on their dependency.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 17-18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Zeller (US 5814272)(previously cited).
With respect to Claim 17, the claim is drawn to a porous sintered metal body “formed by an additive manufacturing method.” Thus, the claim is drawn to a product with a product-by-process limitation reciting the method in which the product was made. According to MPEP § 2113, "Even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In the instant claim, the product-by-process limitation does not introduce any additional structure as no specific additive manufacturing step that might result in a structure differing from a merely sintered metal body is required. As a result, any product formed of sintered metal dendritic particles having the recited porosity is deemed to meet the instant claim, regardless of the manner in which it was manufactured.
Zeller teaches a metal membrane filter element formed by sintering dendritic metal particles, the sintered filter element having a high level of porosity, including examples comprising 60%, 63%, and 65% porosity, respectively. (col. 6, ln. 26-44; col. 7, ln. 49 to col. 8, ln. 27). Furthermore, Zeller teaches an example wherein the metal particles are formed of 316L steel and have a density of 1.54 g/cm3, and thus, have a relative apparent density compared to the bulk/theoretical density of 316L steel (approx. 7.93 g/cm3) of 19.4%, falling within the claimed range. (col. 8, ln. 5-15). Accordingly, Zeller is deemed to teach a porous sintered metal body comprising sintered metal particles having porosity values falling within the claimed ranges with sufficient specificity to anticipate the instant claim.
With respect to Claim 18, Zeller teaches wherein the metal particles are dendritic particles. (see rejection of claim 17 above).
Claim Rejections - 35 USC § 103
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.
Claim(s) 17-18 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Zeller (US 5814272)(previously cited) in view of Buller (US 2017/0239892)(previously cited).
With respect to Claim 17, Zeller teaches a metal membrane filter element formed by sintering dendritic metal particles, the sintered filter element having a high level of porosity, including examples comprising 60%, 63%, and 65% porosity, respectively. (col. 6, ln. 26-44; col. 7, ln. 49 to col. 8, ln. 27). In addition, Zeller teaches an example wherein the metal particles are formed of 316L steel and have a density of 1.54 g/cm3, and thus, have a relative apparent density compared to the bulk/theoretical density of 316L steel (approx. 7.93 g/cm3) of 19.4%, falling within the claimed range. (col. 8, ln. 5-15). It would have been obvious to one of ordinary skill in the art to select metal particles and sintering conditions, from those disclosed by Zeller, resulting in a metal body having a porosity and sintered metal particles having a relative apparent density from the portions of the overlapping ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
In the alternative to the above rejection, if the product-by-process limitation “formed by an additive manufacturing method” is interpreted to require additional structure, Zeller is silent as to wherein the sintered porous metal body detailed above is formed by an additive manufacturing method.
Buller teaches a method of additive manufacturing, wherein the additively manufactured component may be formed of irregular shaped metal particles and exhibits a controlled amount of porosity ranging from 0.05-80%. (para. 2-5, 224, 303). Buller teaches wherein the additive manufacturing method may involve additively forming an object in which successive layers of metal particles are laid down and may involving sintering of the metal particles. (para. 2-5, 162-164).
It would have been obvious to one of ordinary skill in the art to form the sintered porous metal body of Zeller formed from irregular (dendritic) particles, to use a known process of forming a porous sintered metal body from irregular shaped particles, an additive manufacturing process comprising additive deposition and/or fusing in a successive layers, as taught by Buller, in order to more precisely control the final shape, structure, and/or porosity of the sintered body. Moreover, the substitution of method of one method of forming a porous sintered metal body for another would be prima facie obvious to one of ordinary skill in the art.
With respect to Claim 18, Zeller teaches wherein the metal particles are dendritic particles. (see rejection of claim 17 above).
With respect to Claim 20, the porous sintered metal body of Zeller in view of Buller, forming using a layer-by-layer additive manufacturing method, would result in a multi-layer structure visible using an optical microscope. In other words, one of ordinary skill in the art would recognize that such a manufacturing method would leave visible layer-identifying structure(s) where adjacent fused layers were formed. See also MPEP 2112.01.
Claim(s) 17 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Buller (US 2017/0239892)(previously cited).
With respect to Claim 17, the claim requires a sintered metal body having a porosity from 50-80% and also claims wherein the sintered metal particles (no longer particles when in sintered form, and thus, comprising a sintered metal body) have a relative apparent density in a range from 5-35%. These limitations are interpreted such that the values may be drawn to the same or substantially related values. Accordingly, a sintered metal body having a porosity of, for example, 75% may also represent sintered metal particles having relative apparent density of, or approximately, 25%.
Buller teaches a method of additive manufacturing, wherein the additively manufactured component may be formed of irregular shaped metal particles and exhibits a controlled amount of porosity ranging from 0.05-80%. (para. 2-5, 224, 303). Therefore, Buller is deemed to teach a porous sintered metal body having a porosity and relative apparent density of sintered metal particles overlapping the claimed ranges.
Buller teaches wherein the additive manufacturing method may involve additively forming an object in which successive layers of metal particles are laid down and may involving sintering of the metal particles. (para. 2-5, 162-164). Thus, Buller teaches a porous sintered metal body, formed by an additive manufacturing method, comprising sintered metal particles and having a porosity overlapping the instantly claimed range.
It would have been obvious to one of ordinary skill in the art to select from the portion of the overlapping ranges. Overlapping ranges, in particular, where the ranges of a claim overlap with the ranges disclosed in the prior art, have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
With respect to Claim 20, the porous sintered metal body of Buller, forming using a layer-by-layer additive manufacturing method, would result in a multi-layer structure visible using an optical microscope. In other words, one of ordinary skill in the art would recognize that such a manufacturing method would leave visible layer-identifying structure(s) where adjacent fused layers were formed. See also MPEP 2112.01.
Claim(s) 27-28 are rejected under 35 U.S.C. 103 as being unpatentable over Zeller (US 5814272) alone or in the alternative, in view of Buller (US 2017/0239892), as applied to claim 17 above, in view of Hopkins (US 2018/0280848)(previously cited).
With respect to Claims 27-28, Zeller teaches wherein the porous sintered metal body is a filter membrane (see rejections of claim 17 above), but does not explicitly describe the shape of the filter.
Hopkins teaches an annular filter having a shape comprising a three-dimensional tube with a circular cross-section when viewed in a direction of an axis of the tube, wherein the annular filter is formed of a porous metal material and may be made by an additive manufacturing process. (para. 3, 11, 17-18, 36, 48, 51).
Thus, Zeller and Hopkins are both drawn to porous metal bodies for use as a filter. It would have been obvious to one of ordinary skill in the art to modify the porous metal filter membrane of Zeller or Zeller in view of Buller, to be formed into a known filter shape comprising an annular three-dimensional tube with a circular cross-section, as taught by Hopkins, in order to form a useful filter shape for known applications. In other words, it would have been obvious to one of ordinary skill in the art to select a known, conventional, filter shape such as a tube, in order to enhance the utility of the porous sintered metal body filter.
Response to Arguments
Applicant's arguments filed 12/8/2025 have been fully considered but they are not persuasive.
Applicant argues that Zeller (US 5814272) does not disclose metal particles having a relative apparent density in a range of 5 to 35 percent, as required by the amended claim 17. Applicant recites certain exemplary embodiments of Zeller disclosing a measured density, but does not appear to compare these densities to a theoretical density of the particles, and therefore, does not directly assess or argue the relative apparent density of such metal particles. Applicant’s arguments, therefore, are not found persuasive.
Zeller teaches an example wherein the metal particles are formed of 316L steel and have a density of 1.54 g/cm3, and thus, have a relative apparent density compared to the bulk/theoretical density of 316L steel (approx. 7.93 g/cm3) of 19.4%, falling within the claimed range. (col. 8, ln. 5-15).
Moreover, the instant specification recites “Examples of processes useful for producing dendritic metal particles having density properties as described are presented in U.S. Pat. No. 5,814,272, the entirety of which is incorporated herein by reference.” (para. 86 of the PG Pub.). The instant specification, therefore, is interpreted as an admission that Zeller teaches particles having a relative apparent density falling within that disclosed by the instant application. Applicant fails to provide sufficient evidence or argument, commensurate with the scope of the claims, to rebut the prima facie case of anticipation and/or obviousness established by the reference.
Applicant also argues that “Buller does not disclose any density of the particles used to perform the method described” and concludes that Buller fails to teach the limitations of claim 17, as amended. (Remarks, p. 5). These arguments have been fully considered but are not found persuasive.
It is noted that Applicant refers to the density of “particles used to perform the method described.” The currently pending claims are drawn to a product, not a method, and furthermore, recite the relative apparent density of the particles in a sintered state not those used in the method (i.e. initial pre-sintered state).
As detailed above, the amended claim 17 is interpreted such that the porosity and relative apparent density values may be drawn to the same or substantially related values. Additionally, as detailed in the 112(b) rejection, and as evidenced by Applicant’s remarks, it is unclear if the claimed metal particle relative apparent density is a measurement of the particles (thus, pre-sintering) or in a metal body sintered state (and thus, no longer constituting particles). Accordingly, a sintered metal body having a porosity of, for example, 75% may also represent sintered metal particles having relative apparent density of, or approximately, 25%.
Buller teaches a method of additive manufacturing, wherein the additively manufactured component may be formed of irregular shaped metal particles and exhibits a controlled amount of porosity ranging from 0.05-80%. (para. 2-5, 224, 303). Therefore, Buller is deemed to teach a porous sintered metal body having a porosity and relative apparent density of sintered metal particles overlapping the claimed ranges. Overlapping ranges, in particular, where the ranges of a claim overlap with the ranges disclosed in the prior art, have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN A HEVEY whose telephone number is (571)270-0361. The examiner can normally be reached Monday-Friday 9:00-5:30.
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/JOHN A HEVEY/Primary Examiner, Art Unit 1735