Prosecution Insights
Last updated: April 19, 2026
Application No. 18/631,151

Peritoneal Dialysis Systems, Devices, and Methods

Final Rejection §112
Filed
Apr 10, 2024
Examiner
NGUYEN, BOI-LIEN THI
Art Unit
1779
Tech Center
1700 — Chemical & Materials Engineering
Assignee
NxStage Medical, Inc.
OA Round
2 (Final)
25%
Grant Probability
At Risk
3-4
OA Rounds
3y 10m
To Grant
75%
With Interview

Examiner Intelligence

Grants only 25% of cases
25%
Career Allow Rate
13 granted / 52 resolved
-40.0% vs TC avg
Strong +50% interview lift
Without
With
+50.4%
Interview Lift
resolved cases with interview
Typical timeline
3y 10m
Avg Prosecution
45 currently pending
Career history
97
Total Applications
across all art units

Statute-Specific Performance

§103
49.5%
+9.5% vs TC avg
§102
19.5%
-20.5% vs TC avg
§112
30.3%
-9.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 52 resolved cases

Office Action

§112
DETAILED ACTION This detailed action is in response to the amendments and arguments filed on 01/07/2026, and any subsequent filings. Notations “C_”, “L_” and “Pr_” are used to mean “column_”, “line_” and “paragraph_”. Claims 1-17 are pending. Claims 1-2 are previously withdrawn. Notice of Pre-AIA or AIA Status The present application is being examined under the pre-AIA first to invent provisions. Response to Amendment 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. Claim 3-6 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. Claim 3 reads “integrally connected, without connectors” and such language appears to be absent from the originally filed specification. Dependent claims not recited above require all of the limitations of independent Claim 3, and therefore are rejected for the same reasons set forth above. Allowable Subject Matter Claims 7-17 are allowed. The following is a statement of reasons for the indication of allowable subject matter: The present invention is related to a method of preparing a treatment fluid, comprising: activating a flow switch to connect a first fluid concentrate to a pump and flowing the first fluid concentrate through the pump into a batch container at a first pumping rate; activating the flow switch to connect a second fluid concentrate to the pump and flowing the second fluid concentrate through the pump into the batch container at a second pumping rate; activating the flow switch to connect a diluent fluid source to the pump and flowing the diluent fluid through the pump into the batch container at a third pumping rate; controlling a pumping rate of the pump to maintain constant pumping rates wherein the first pumping rate, the second pumping rate, and third pumping rate are identical to each other and held constant during the pumping. U.S. Publication US20090182263A1 (‘Burbank’) is considered the closest prior art. Burbank teaches a method of preparing a treatment fluid (abstract), comprising: activating a flow switch (Fig. 19A, [0139], path selector, pumping, and short term filter portion 1315) to connect a first fluid concentrate to a pump (Fig. 19A, [0139], line 1366 provides connection to containers of medicament concentrate 1310) and flowing the first fluid concentrate through the pump into a batch container at a first pumping rate ([0207]); activating the flow switch to connect a second fluid concentrate to the pump (Fig. 19A, [0139], line 1366 provides connection to containers of medicament concentrate 1310) and flowing the second fluid concentrate through the pump into a batch container at a second pumping rate ([0207]); activating the flow switch to connect a diluent fluid source to the pump (Fig. 19A, [0143], line 1370 provides water) and flowing the diluent fluid through the pump into the batch container at a third pumping rate ([0143]). Burbank does not teach controlling a pumping rate of the pump to maintain constant pumping rates wherein the first pumping rate, the second pumping rate, and third pumping rate are identical to each other and held constant during the pumping. Accordingly, there does not appear to be any reasonable basis for the skilled artisan to be directed towards the aforementioned claim limitations of the instant 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 BOI-LIEN THI NGUYEN whose telephone number is (703)756-4613. The examiner can normally be reached Monday to Friday, 8 am to 6 pm. 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, Bobby Ramdhanie can be reached at (571) 270-3240. 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. /BOI-LIEN THI NGUYEN/Examiner, Art Unit 1779 /Bobby Ramdhanie/Supervisory Patent Examiner, Art Unit 1779
Read full office action

Prosecution Timeline

Apr 10, 2024
Application Filed
Oct 02, 2025
Non-Final Rejection — §112
Jan 07, 2026
Response Filed
Feb 17, 2026
Final Rejection — §112 (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

3-4
Expected OA Rounds
25%
Grant Probability
75%
With Interview (+50.4%)
3y 10m
Median Time to Grant
Moderate
PTA Risk
Based on 52 resolved cases by this examiner. Grant probability derived from career allow rate.

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