Prosecution Insights
Last updated: April 18, 2026
Application No. 18/515,679

OPTICAL FIBER CABLE HAVING LOW FREE SPACE AND HIGH FIBER DENSITY

Non-Final OA §103
Filed
Nov 21, 2023
Examiner
CHU, CHRIS H
Art Unit
2874
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Corning Research & Development Corporation
OA Round
1 (Non-Final)
53%
Grant Probability
Moderate
1-2
OA Rounds
2y 12m
To Grant
63%
With Interview

Examiner Intelligence

Grants 53% of resolved cases
53%
Career Allow Rate
345 granted / 650 resolved
-14.9% vs TC avg
Moderate +10% lift
Without
With
+10.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 12m
Avg Prosecution
44 currently pending
Career history
694
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
74.2%
+34.2% vs TC avg
§102
20.0%
-20.0% vs TC avg
§112
1.8%
-38.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 650 resolved cases

Office Action

§103
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. DETAILED ACTION Election /Restrictions Applicant's election with traverse of claims 1-11 in the reply filed on March 12, 2026 is acknowledged. The traversal is on the ground(s) that claim 12 has been amended to require “each optical fiber comprising a fiber diameter of 160 microns to 200 microns” . This is not found persuasive because claim 12 still does not require an interior surface defining a buffer tube cross-sectional area or a free space of at least 37%. The requirement is still deemed proper and is therefore made FINAL. Information Disclosure Statement The information disclosure statements (IDS) submitted on December 11, 2023 and March 19, 2025 have been considered by the examiner. Drawings Six sheets for formal drawings were filed November 21, 2023 and have been accepted by the Examiner. Specification Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification. 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 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 of this title, 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 set forth in Graham v. John Deere Co. , 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 -11 are rejected under 35 U.S.C. 103 as being unpatentable over Bookbinder et al. (US 2019/0293885 A1 from Applicant’s Information Disclosure Statement filed December 11, 2023 ). Regarding claim 1 , Bookbinder discloses an optical fiber cable (10 in Fig. 1) , comprising: a cable jacket (12) comprising an inner surface and an outer surface, the inner surface defining a central cable bore and the outer surface defining an outermost surface of the optical fiber cable and a cable cross-sectional area; at least one buffer tube (22) disposed within the central cable bore, each buffer tube of the at least one buffer tube comprising an interior surface defining a buffer tube cross-sectional area; a plurality of optical fibers ( 20 ) disposed within the at least one buffer tube; wherein each optical fiber of the plurality of optical fibers comprises a fiber diameter of 160 microns to 200 microns (Table 5, Example 11 discloses a fiber diameter of 170 microns) ; wherein the plurality of optical fibers comprise a total fiber area AF (See Figs. 1, 2A-2C ); and wherein the optical fiber cable comprises a fiber density (N/Ac) of at least 3.25 fibers/mm 2 (Table 5, Example 11 discloses a fiber density of 14.36 fibers/mm 2 ). Still r egarding claim 1 , Bookbinder teaches the claimed invention except for specifically stating the free space . However, Bookbinder discloses in paragraph 0026 that bend losses are greater when optical fibers are densely packed and buffer tubes should include a significant amount of free space to assume low stress positions. As such, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to arrive at the claimed free space , since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller , 105 USPQ 233. Regarding claim 2 , Bookbinder discloses the at least one buffer tube comprises six or more buffer tubes in Fig. 1. Regarding claim 3 , Bookbinder discloses the plurality of optical fibers comprises from twelve to thirty-six optical fibers in Fig. 1. Regarding claim 4 , Bookbinder teaches the claimed invention except for specifically stating a fiber density from 3.5 fibers/mm 2 to 6 fibers/mm 2 . However, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to arrive at the claimed fiber density, since Bookbinder discloses other fibers having a fiber density from 3.5 fibers/mm 2 to 6 fibers/mm 2 (see Table 5, Examples 2, 4 and 5), and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller , 105 USPQ 233. Regarding claim 5 , Bookbinder discloses the buffer tubes are disposed around a central strength member (24) in Fig. 1. Regarding claim 6 , Bookbinder discloses each optical fiber of the plurality of optical fibers comprises a germania-doped silica core (paragraph 0099) and a fluorine-doped silica trench (paragraph 0078). Regarding claim 7 , Bookbinder discloses the fluorine-doped silica trench is rectangular in Fig. 10. R egarding claim 8, Bookbinder teaches the claimed invention except for the trench being triangular . However, different shaped trenches are well-known and commonly used in the art of optical fibers and as such, one of ordinary skill in the art before the effective filing date of the claimed invention wou ld have found it obvious to use a triangular-shaped trench as a matter of obvious design choice without inventive skill. Regarding claim 9 , Bookbinder discloses a trench volume of from 25% Δ microns 2 to 70% Δ microns 2 in paragraphs 0083-0084. R egarding claim 10 , Bookbinder teaches the claimed invention except for specifically stating the free space . However, Bookbinder discloses in paragraph 0026 that bend losses are greater when optical fibers are densely packed and buffer tubes should include a significant amount of free space to assume low stress positions. As such, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to arrive at the claimed free space, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller , 105 USPQ 233. 11. R egarding claim 1 1 , Bookbinder discloses the optical fiber comprising a bend loss of less than 0.5 dB/turn at 1550 nm for one bend around a mandrel of diameter of 15 mm, a bend loss of less than 0.1 dB/turn at 1550 nm for one bend around a mandrel of diameter of 20 mm, and a bend loss of less than 0.003 dB/turn at 1550 nm for one bend around a mandrel of diameter of 30 mm (see paragraph 0086 and Table 2, Example 4) . Further, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to minimize bend losses, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller , 105 USPQ 233. 11. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to FILLIN "Examiner name" \* MERGEFORMAT CHRIS H CHU whose telephone number is FILLIN "Phone number" \* MERGEFORMAT (571)272-8655 . The examiner can normally be reached on FILLIN "Work schedule?" \* MERGEFORMAT Mon-Fri 9AM-5PM . If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Uyen-Chau Le can be reached on FILLIN "SPE Phone?" \* MERGEFORMAT 571-272-2397 97. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Any inquiry of a general or clerical nature should be directed to the Technology Center 2800 receptionist at telephone number (571) 272-1562. Chris H. Chu /CHRIS H CHU/ Primary Examiner, Art Unit 2874 March 25, 2026
Read full office action

Prosecution Timeline

Nov 21, 2023
Application Filed
Mar 25, 2026
Non-Final Rejection — §103 (current)

Precedent Cases

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

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Prosecution Projections

1-2
Expected OA Rounds
53%
Grant Probability
63%
With Interview (+10.1%)
2y 12m
Median Time to Grant
Low
PTA Risk
Based on 650 resolved cases by this examiner. Grant probability derived from career allow rate.

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