Prosecution Insights
Last updated: April 19, 2026
Application No. 17/307,572

OPTICAL GLASS WITH LOW DENSITY

Final Rejection §102§103
Filed
May 04, 2021
Examiner
BOLDEN, ELIZABETH A
Art Unit
1731
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Schott AG
OA Round
5 (Final)
85%
Grant Probability
Favorable
6-7
OA Rounds
2y 9m
To Grant
99%
With Interview

Examiner Intelligence

Grants 85% — above average
85%
Career Allow Rate
794 granted / 932 resolved
+20.2% vs TC avg
Strong +22% interview lift
Without
With
+22.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
24 currently pending
Career history
956
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
24.7%
-15.3% vs TC avg
§102
32.2%
-7.8% vs TC avg
§112
23.8%
-16.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 932 resolved cases

Office Action

§102 §103
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 . In the event the determination of the status of the application as subject to AIA 35 U.S.C. 112, 102, and 103 (or as subject to pre-AIA 35 U.S.C. 112, 102, and 103) is incorrect, any correction of the statutory basis 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. Status of the Claims Any rejections and or objections, made in the previous Office Action, and not repeated below, are hereby withdrawn. Claims 1-3, 5-7, 9-16, 18, 19, 23, and 24 are currently pending. Claims 13-16, 18, 19, and 24 have been withdrawn. Claims 4, 8, 17, and 20-22 have been cancelled. Claims 1-3, 5-7, 9-12, and 23 are currently rejected. Claims 1-3, 5-7, 9-12, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Nagaoka, JP 2010-006676 A. Information Disclosure Statement The information disclosure statement (IDS) submitted on 12 November 2025has been considered by the examiner. Claim Comment The Claim Status indicator of claim 24 currently reads “Previously Presented” and should read “Withdrawn”. 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. 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. Claims 1-3, 5-7, 9-12, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Nagaoka, Japanese Patent Publication JP 2010-006676 A. A machine-generated translation of JP 2010-006676 A accompanied the previous action. In reciting this rejection, the examiner will cite this translation. Nagaoka teaches an optical glass comprising in terms of weight percent: 5-55% of TiO2, 0-25% of SiO2, 0-10% of B2O3, 0-50% of Nb2O5, 0-40% of Bi2O3, 0-25% of MgO, 0-25% of CaO, 0-25% of SrO, 0-25% of BaO, 0-25% of ZnO, 0-10% of Li2O, 0-20% of Na2O, 0-10% of K2O, 0-10% of Cs2O, 0-10% of Rb2O, 0-10% of Al2O3, 0-10^% of Y2O3, 0-10% of La2O3, 0-10% of Gd2O3, 0-10% of Yb2O3, 0-10% of Lu2O3, 0-15% of ZrO2, 0-15% of Ta2O5, 0-15% of WO3, 0-10% of TeO2, 0-15% of GeO2, 0-10% of P2O5, and 0-1% of Sb2O3. See Abstract and the entire specification, specifically, paragraphs [0009]-[0017]. Nagaoka discloses the optical glass has an Abbe number of 13-27. See paragraph [0009]. Nagaoka teach that the glasses have a refractive in in the range of 1.862-1.901. See the refractive indexes of the Examples in Table 1. Nagaoka discloses that when the transmittance is 5% the wavelength is preferably less 400 nm and when the transmittance is 70% the wavelength is preferably less than 480 nm. See paragraph [0070]. As to claim 1, Nagaoka teaches an optical glass comprising in terms of weight percent: 5-55% of TiO2, 0-25% of SiO2, 0-10% of B2O3, 0-50% of Nb2O5, 0-40% of Bi2O3, 0-25% of MgO, 0-25% of CaO, 0-25% of SrO, 0-25% of BaO, 0-25% of ZnO, 0-10% of Li2O, 0-20% of Na2O, 0-10% of K2O, 0-10% of Cs2O, 0-10% of Rb2O, 0-10% of Al2O3, 0-10^% of Y2O3, 0-10% of La2O3, 0-10% of Gd2O3, 0-10% of Yb2O3, 0-10% of Lu2O3, 0-15% of ZrO2, 0-15% of Ta2O5, 0-15% of WO3, 0-10% of TeO2, 0-15% of GeO2, 0-10% of P2O5, and 0-1% of Sb2O3. See paragraphs [0009]-[0017]. Nagaoka teaches Example 4 in Table 1 which comprises in terms of weight % 22.38% of TiO2, 21.67% of SiO2, 31.04% of Nb2O5, 14.28% of BaO, 9.84% of Na2O, 0.78% of ZrO2, and 0.02% of Sb2O3 and nearly anticipates claim 1. Nagaoka fails to teach any examples or compositional ranges that are sufficiently specific to anticipate the compositional limitations of claim 1, However, the weight percent ranges taught by Nagaoka have overlapping compositional ranges with instant claim 1, 3, 5, and 9-12. See paragraphs [0009]-[0017]. Nagaoka teaches that CaO can be added to the glass in amounts up to 25.0% in order to control the dispersion, specific gravity, and refractive index of the glass. See paragraph [0032]. Overlapping ranges have been held to establish prima facie obviousness. See MPEP 2144.05. It would have been obvious to one of ordinary skill in the art before the effective filing date to have selected from the overlapping portion of the ranges disclosed by Nagaoka because Nagaoka teaches that the addition of CaO allows the dispersion, specific gravity, and refractive index to be controlled. Therefore, the compositional ranges of Nagaoka as taught in paragraphs [0009]-[0017] and [0032] reads on an optical glass comprising 6-35% of SiO2, 0-12% of B2O3, 20-55% of Nb2O5, 10-50% of TiO2, 0-5% of ZrO2, 0-5% of Al2O3, 0-12% of ZnO, 0.1-12% of CaO, 0.1-35% of BaO, 0-8% of SrO, 0-20% of Na2O, 0-25% of K2O, 0-2% of Sb2O3, and 0-2% of As2O3, as recited in claim 1. Nagaoka further discloses that Example 4 which nearly anticipates the compositional limitations of claim1 has a refractive index of 1.892 and an Abbe number of 22.1, which reads on a refractive index of 1.85-2.00 and an Abbe number (or dispersion) of 19.0-27.0 as recited in instant claim 1. Nagaoka discloses Example 4 has a l5 of 374 nm and a l70 of 421 nm. Since the optical glass of the reference is the same as those claimed herein it follows that the optical glasses of Nagaoka would inherently possess the density for the ratio of r/nd and the internal transmission at 450 nm property as recited in claim 1. See MPEP 2112. It is well settled that when a claimed composition appears to be substantially the same as a composition disclosed in the prior art, the burden is properly upon the applicant to prove by way of tangible evidence that the prior art composition does not necessarily possess characteristics attributed to the CLAIMED composition. In re Spada, 911 F.2d 705, 15 USPQ2d 1655 (Fed. Circ. 1990); In re Fitzgerald, 619 F.2d 67, 205 USPQ 594 (CCPA 1980); In re Swinehart, 439 F.2d 2109, 169 USPQ 226 (CCPA 1971). Products of identical composition may not have mutually exclusive properties. In re Spada 15 USPQ2d 1655,1658 (Fed. Circ. 1990). As to claim 2, Nagaoka discloses Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) having a refractive index of 1.892, which reads in a refractive index of 1.85-1.95 as recited in claim 2. As to claim 3, Nagaoka discloses that the glass of Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has no Ta2O5, no GeO2, and no WO3, which reads on the glass comprising at least one of Ta2O5, WO3, and GeO2 being less than 5wt% as recited in claim 3. As to claim 5, Nagaoka discloses that Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has a TiO2 content of 22.38 wt%, a Nb2O5 content of 31.04 wt%, and a BaO content of 14.28 wt%, with a total of the 3 components being 67.7, which reads on the sum of Nb2O5+TiO2+BaO being at least 45 wt% as recited in claim 5. As to claim 6, Nagaoka discloses that the optical glass has a Tg of less than or equal to 700°C, (see paragraph [0074]), which reads on a Tg of 500-650°C as recited in claim 6. As to claim 7, Nagaoka discloses that the glass of Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has no B2O3 and therefore 0 B3+ cations, which reads on a ratio of B3+/Si4+ of at most 2.5 g/cm3 as recited in claim 7. As to claim 9, Nagaoka disclose Example 4 in Table 1 which comprises in terms of weight % 22.38% of TiO2, 21.67% of SiO2, 31.04% of Nb2O5, 14.28% of BaO, 9.84% of Na2O, 0.78% of ZrO2, and 0.02% of Sb2O3, and that the glass may further include 0-25% of CaO (paragraph[0032]), which reads on an optical glass comprising 6-35% of SiO2, 0-12% of B2O3, 20-55% of Nb2O5, 10-50% of TiO2, 0-5% of ZrO2, 0-5% of Al2O3, 0-12% of ZnO, 0.1-12% of CaO, 1.0-35% of BaO, 0-8% of SrO, 0-20% of Na2O, 0-25% of K2O, 0-2% of Sb2O3, and 0-2% of As2O3, as recited in claim 9. As to claim 10, Nagaoka disclose Example 4 in Table 1 which comprises in terms of weight % 22.38% of TiO2, 21.67% of SiO2, 31.04% of Nb2O5, 14.28% of BaO, 9.84% of Na2O, 0.78% of ZrO2, and 0.02% of Sb2O3 and that the glass may further include 0-25% of CaO (paragraph[0032]), which reads on an optical glass comprising 10-29% of SiO2, 0-8% of B2O3, 20-45% of Nb2O5, 15-40% of TiO2, 0-2% of ZrO2, 0-2% of Al2O3, 0-8% of ZnO, 0.1-6% of CaO, 2.0-22% of BaO, 0-5% of SrO, 2-15% of Na2O, 0-18% of K2O, 0-0.3% of Sb2O3, and 0-0.3% of As2O3, as recited in claim 10. As to claim 11, Nagaoka disclose that the glass of Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has no La2O3, no Gd2O3, no Y2O3, no GeO2, no Ta2O5, no MgO, no Li2O, 0.78 wt% of ZrO2, no P2O5, and no WO3, which reads on the glass being substantially free of at least one of La2O3, Gd2O3, Y2O3, GeO2, Ta2O5, MgO, Li2O, ZrO2,P2O5, and WO3 as recited in claim 11. As to claim 12, Nagaoka disclose that the glass of Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has no lead, no bismuth, no cadmium, no nickel, 020 wt% of As2O3,and no antimony, which reads on the glass being substantially free of at least one of lead, bismuth, cadmium, nickel, arsenic, and antimony as recited in claim 12. As to claim 23, Nagaoka discloses that Example 4 and that the glass may further include 0-25% of CaO (paragraph[0032]) has a TiO2 content of 22.38 wt% and a Nb2O5 content of 31.04 wt%, with a ratio of Nb2O5/TiO2 of 1.39, which reads on the ratio of Nb2O5/TiO2 being between 0.72 and 3.5 as recited in claim 23. Response to Arguments Applicant’s arguments, see pages 8-10, filed 4 December 2025, with respect to the rejection(s) of claim(s) 1-3, 5-7, 9-12, and 23 under 35 USC 102(a)(1) have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of 35 USC 103 that the compositional ranges overlap and therefore render obvious the instant claims. The Applicant further argues that the glass of Nagaoka does not disclose the density of any of the glasses. This is not found persuasive since a glass having overlapping compositional limitations would be expected to have overlapping properties absent evidence to the contrary. The Examiner will consider rejoinder of the withdrawn claims once the elected claims have been indicated allowable and the scope of the withdrawn claims in instep with the elected claims. 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 Elizabeth A. Bolden whose telephone number is (571)272-1363. The examiner can normally be reached 10:00 am to 6:30 pm M-F. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Amber R. Orlando can be reached at 571-270-3149. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /Elizabeth A. Bolden/Primary Examiner, Art Unit 1731 EAB 24 February 2026
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Prosecution Timeline

May 04, 2021
Application Filed
Jan 25, 2024
Non-Final Rejection — §102, §103
Apr 30, 2024
Response Filed
Jun 25, 2024
Final Rejection — §102, §103
Aug 30, 2024
Response after Non-Final Action
Oct 01, 2024
Request for Continued Examination
Oct 04, 2024
Response after Non-Final Action
Oct 30, 2024
Non-Final Rejection — §102, §103
Feb 04, 2025
Response Filed
Jul 31, 2025
Non-Final Rejection — §102, §103
Dec 04, 2025
Response Filed
Feb 24, 2026
Final Rejection — §102, §103 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

6-7
Expected OA Rounds
85%
Grant Probability
99%
With Interview (+22.3%)
2y 9m
Median Time to Grant
High
PTA Risk
Based on 932 resolved cases by this examiner. Grant probability derived from career allow rate.

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