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 3/5/2026, is acknowledged. Claims 1 and 3-5 are amended; Claim 2 is canceled. Claims 1 and 3-9 are currently pending, claims 6-9 are withdrawn.
The rejection of claims 1-3 and 5 under 35 U.S.C. 112(b) is withdrawn in view of Applicant’s amendments to the claims. The 112(b) rejection of claim 4 is maintained, as detailed below.
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.
Claim 4 is 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 4 recites the limitation “a tensile strength of 650 MPa or more even after the PWHT at 750 to 850°C for 10 to 50 hours.” There is insufficient antecedent basis for the limitation “the PWHT” in the claim. Furthermore, the phrase “even after” renders the claim indefinite. It is unclear how the word “even” limits the scope of the claimed property and/or the process condition it is associated with.
Applicant’s remarks, filed 3/5/2026, state an intention to amend the claim to “a PWHT” and to delete the word “even”; however, no such amendment was filed.
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) 1 and 3-5 are rejected under 35 U.S.C. 103 as being unpatentable over Oura (JP 2020-020031A)(machine translated previously provided).
With respect to Claims 1 and 3, Oura teaches a steel plate with a composition, in weight%, as follows (pgs. 1, 3-6 of translation):
Claim 1
Oura
C
0.10-0.16
≤ 1.0
Si
0.20-0.35
≤ 3.0
Mn
0.4-0.6
0.2-7.0
Cr
7.5-8.5
0-10
Mo
0.7-1.0
0-2.0
Al
0.005-0.05
≤ 3.0
P
≤ 0.015
≤ 0.10
S
≤ 0.002
≤ 0.030
Nb
0.001-0.025
0-1.0
V
0.25-0.35
0-1.0
Fe
Balance with unavoidable impurities
Balance with impurities
Compositional ranges including zero are interpreted as optional elements. Thus, Oura teaches a steel plate with a composition overlapping each of the instantly claimed ranges. 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 claimed composition 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 the preamble limitation “A pressure vessel steel plate,” the claim requires a steel composition in the form of a plate, and the term “pressure vessel” is not interpreted to impart additional structure. In other words, the claim does not require a pressure vessel itself but merely a “plate” for a pressure vessel. Therefore, the limitation is interpreted as a statement of the intended use of the steel plate. Therefore, the limitation is interpreted as a statement of the intended use of the steel plate. A recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Here, Oura teaches the steel in the form a plate, and therefore, is deemed capable of the recited intended use.
Finally, with respect to the claim 1 limitation drawn to “a mixed structure of tempered martensite and tempered bainite” and the limitations of Claim 3, the claims each use the open transitional phrase “comprising” and therefore, the recited limitations drawn to the microstructure of the steel plate are interpreted to allow additional, unrecited, microstructural phases. Oura teaches wherein the steel has a total volume of tempered martensite and tempered bainite of 90% or more and a content of martensite (not tempered) of 5-40%. (abstract). Thus, Oura teaches a mixed structure of tempered martensite and tempered bainite as in claim 1, and teaches a range of tempered martensite of tempered bainite, each present in an amount of 0-90% such that the total is 90% or more, overlapping the claimed ranges of claim 3. Overlapping ranges, in particular, where the ranges of a claimed composition 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 4, Oura teaches exemplary embodiments wherein each embodiment exhibited a tensile strength of more than 650 MPa, with certain examples exceeding 1000 MPa, and teaches that the steel is subjected to heat treatments at temperatures of 750°C or more. (Tables 2 and 4). Therefore, while Oura may not teach a tensile strength measurement under the specific PWHT conditions recited in the claim, as the reference teaches a steel with overlapping composition and drawn to a tensile strength far exceeding the required value, it would be expected to necessarily result in the same properties, including the claimed tensile strength under the claimed PWHT conditions. "Where 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.” In re Best, 195 USPQ 430, 433 (CCPA 1977). Thus, the burden is shifted to the applicant to prove that the product of the prior art does not necessarily or inherently possess the characteristics attributed to the claimed product. See In re Spada, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990) (“When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not."); MPEP 2112.01. Therefore, the prima facie case can only be rebutted by evidence showing that the prior art products do not necessarily possess the characteristics of the claimed product.
With respect to Claim 5, Oura is silent as to a Charpy impact energy test measurement. However, as the reference teaches a steel with overlapping composition, structure, and drawn to shared properties such as high tensile strength, it would be expected to necessarily result in the same Charpy impact energy properties. See MPEP 2112.01.
Response to Arguments
Applicant’s arguments, filed 3/5/2026, with respect to the rejection of claims 1 and 4-5 under 35 U.S.C. 103 over Yamashita have been fully considered and are persuasive in view of Applicant’s amendments to the claims. Specifically, Yamashita fails to teach a steel plate having a mixed structure of tempered martensite and tempered bainite. The rejection has been withdrawn.
Applicant's arguments filed 3/5/2026 with respect to the rejection of claims 1-5 under 35 U.S.C. 103 over Oura have been fully considered but they are not persuasive.
Applicant argues that prior art Oura requires a microstructure comprising fresh martensite, and therefore, fails to meet claim 1, as amended. This argument is not found persuasive.
Claim 1 recites “wherein a structure of the steel plate is comprised of a mixed structure of tempered martensite and tempered bainite.” The recited limitation uses the open transitional phrase “comprising” and therefore, the microstructure of the steel plate is interpreted to allow additional, unrecited, microstructural phases. Thus, a prior art reference containing additional phase(s) still meets the claimed limitation as long as it also contains the required phases of tempered martensite and tempered bainite.
Oura teaches wherein the steel has a total volume of tempered martensite and tempered bainite of 90% or more and a content of martensite (not tempered) of 5-40%. (abstract). Thus, Oura teaches a mixed structure of tempered martensite and tempered bainite meeting claim 1.
Applicant also argues that the method of making disclosed by Oura differs from that disclosed for the instantly claimed steel plate. Applicant concludes that the prior art would not, therefore, possess a microstructure meeting claim 1. These arguments have been fully considered but are not found persuasive.
Claim 1 does not require any product-by-process limitations nor does the rejection of claim 1 rely on the method of making to demonstrate the claimed mixed microstructure of tempered martensite and tempered bainite. As detailed above, Oura teaches a steel plate meeting the claimed microstructure of claim 1. Therefore, even if the reference discloses a method of making differing from that in the instant specification, it meets the claim.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., a particular method of making) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Conclusion
Applicant's amendment necessitated any 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