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 .
Reissue Applications
For reissue applications filed on or after September 16, 2012, all references to 35 U.S.C. 251 and 37 CFR 1.172, 1.175, and 3.73 are to the current provisions. This application, filed March 8, 2021 is a reissue continuation of Serial No. 15/431,665 (the ‘665 reissue application), filed February 13, 2017, now U.S. Patent RE48,464, which is a reissue of U.S. Patent 9,024,016 (hereafter the '016 patent), which issued from U.S. application Serial No. 13/901,735 (the ‘735 application) with claims 1-11 on May 5, 2015.
Application Data Sheet
The application data sheet (ADS) filed on March 8, 2021, is objected to because the domestic benefit information does not properly identify the present application as a reissue application of U.S. patent 9,024,016 (which issued from application no. 13/901,735). See the Reissue Application Filing Guide at https://www.uspto.gov/sites/default/files/forms/uspto_reissue_ads_guide_Sept2014.pdf and in particular see the screen shot on page 10 given the sample facts presented on page 9. A corrected ADS is required.
The corrected ADS should comply with 37 CFR 1.76(c)(2), which requires that any changes to an ADS be identified with markings (underline for addition, strike through for deletion). A request for corrected filing receipt is not required.
Claims Under Reissue
During patent examination, the pending claims must be “given their broadest reasonable interpretation consistent with the specification. In re Reuter, 651 F.2d 751, USPQ 249 (CCPA 1981) (claims given "their broadest reasonable interpretation consistent with specification"). This reissue application contains claims 137-143 and 145-178 filed 11/05/2025. Claims 137 is independent and representative:
137. (New, Currently Amended) A process for producing acesulfame potassium, the process comprising:
(a) reacting a first reaction mixture comprising sulfamic acid, an amine, and from 1 wppm to 1 wt.% acetic acid to form an amidosulfamic acid salt, wherein the pH of the first reaction mixture is from 5.9 to 6.8, the molar ratio of amine to sulfamic acid in the first reaction mixture is from 1:1 to 1.05:1, and the molar ratio of the acetic acid to the sulfamic acid is less than 0.095:1;
(b) reacting a second reaction mixture comprising the amidosulfamic acid salt and diketene to form an acetoacetamide salt; and
(c) deriving the acesulfame potassium from the acetoacetamide salt.
Claim Rejections - 35 USC §§ 102 and 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 (i.e., changing from AIA to pre-AIA ) 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 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.
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.
Claims 137, 139, 141-142, 146-147, 149-153, 155-156 and 158-177 are rejected under 35 U.S.C. 102(a)(1) as being in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention, or alternatively under 35 U.S.C. 103 as being an obvious variant thereof.
In the Remarks filed 11/05/2025, Applicant states that the process in reissue claims 137, 139, 141-142, 144, 146-147, 149-153, 155-156, 158-161, 168-170, and 172-177 filed before the Office action mailed 05/05/2025, i.e., the process in claims 137, 139, 141-142, 144, 146-147, 149-153, 155-156, 158-161, 168-170 filed 07/17/2024, was performed in its facility in Frankfurt, Germany (hereinafter the “Frankfurt process”) from the time period of 2008-2013. In other words, the Frankfurt process was used from 2008-1013 to prepare a commercially available product in said time period.
Reissue claim 137 filed 11/05/2025 and its dependent claims differ from the Frankfurt process since they require that the molar ratio of amine to sulfamic acid in the first reaction mixture is 1:1 to 1.05:1. The Frankfurt process used a ratio of 1.052:1 or greater. In particular, on p. 8 of the Remarks filed 11/05/2025, Applicant states:
Without wishing to acquiesce to the propriety of said rejection, Applicant has amended independent claim 137 to include the requirement that the molar ratio of amine to sulfamic acid is from 1:1 to 1.05:1 (previously recited in dependent claim 143 [filed 07/17/2024]). Based on current information and belief, molar ratios of 1.052 or greater were used at the facility in Frankfurt, Germany prior to 2013.
However, the molar ratio of 1.052:1 (also referred to as “1.052”), reads on the claimed upper limit of 1.05:1 (also referred to as “1.05”). In particular, instead of using three decimal places as in the molar ratio of the Frankfurt process, current reissue claim 137 and its dependent claims, as well as the ‘016 patent specification, use less precision, i.e. two decimal places, for the ratio of amine to sulfamic acid (see, e.g., col. 6, lines 14-16).
The 1.052 ratio in the Frankfurt process rounded to two decimal places as here claimed is 1.05, and thus, is the same as here claimed.
Also, the yellowness index of the amidosulfamic acid salt in claims 162-164, the yellowness index of the acetoacetamide salt in claims 165-167 and 171, and the yellowness index of the acesulfame potassium in claims 168-170, are inherent in the Frankfurt process since it has the same process steps as here claimed.
Since the Frankfurt process was performed to prepare a commercial product more than one year prior to the claimed process and is the same process as here claimed, reissue claims 137, 139, 141-142, 146-147, 149-153, 155-156 and 158-177 are unpatentable under 35 USC 102(a)(1). It has been held that the sale of a product produced by a secret process is invalidating to claims to the process, and rejection under 35 USC §102(a)(1) is appropriate. See MPEP §2152.02(d) and Celanese International Corporation v. ITC, 111 F.4th 1338 (Fed. Cir. 2024).
Alternatively, to any extent there is a difference between the claimed ratio of 1:1 to 1.05:1 and the Frankfurt process’s 1.052:1 or greater, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. See Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985) and MPEP 2144.05.I. The 1.052 and 1.05 are so close that prima facie one skilled in the art would have expected them to result in the same product or substantially the same product. It is noted that prior art under the § 102 on-sale bar is also prior art for the purposes of obviousness under § 103. See e.g., Dippin’ Dots, 476 F.3d 1337 (Fed. Cir. 2007) and Pfaff v. Wells Elecs., Inc., 525 U.S. 55 (Fed. Cir. 1998).
As a further alternative with respect to the claimed ratio of 1:1 to 1.05:1, it would have been obvious to one of ordinary skill in the art vary the 1.052:1 or greater ratio of amine to sulfamic acid in the first reaction mixture of the Frankfurt process and arrived at a ratio here claimed through routine experimentation and/or so as to optimize the reaction. Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. See MPEP 2144.05.II.A. Additionally, upon modification of the Frankfurt process, the yellowness indexes of instant claims 162-171 would have been present since the instantly claimed process would be performed.
Accordingly, claims 137, 139, 141-142, 146-147, 149-153, 155-156 and 158-177 are unpatentable under 35 USC 103.
Claims 138, 140, 143, 145, 148, 154 and 157 are rejected under 35 U.S.C. 103 as being unpatentable over the Frankfurt process.
The Frankfurt process is relied upon for the reasons stated above.
With respect to claim 138, the Frankfurt process does not require the pH of the first reaction mixture is from 6.1 to 6.4. However, the Frankfurt process performed the process of claim 137 filed 07/17/2024. Claim 137 filed 07/17/2024 sets forth a first reaction mixture pH of from 5.9 to 6.8. The claimed pH range of 6.1 to 6.4 lies inside said pH range of from 5.9 to 6.8.
It would have been obvious to one of ordinary skill in the art to have varied the pH of the first reaction mixture in the Frankfurt process and arrived at a pH here claimed through routine experimentation and/or so as to optimize the reaction. In view of the fact that there’s amine and acetic in the reaction mixture, it would have been obvious for a skilled artisan to have optimized reaction pH.
With respect to claim 140, the Frankfurt process performed the process of claim 141 filed 07/17/2024. The process in claim 141 uses a solvent in the first reaction mixture, and from 1 wppm (i.e., 0.0001 wt%) to 1 wt% acetic acid in the first reaction mixture. The Frankfurt process does not use acetic acid in an amount of less than 0.175 wt% in the first reaction mixture based on the total weight of sulfamic acid, amine, acetic acid and solvent.
It would have been obvious to one of ordinary skill in the art to have varied the acetic acid concentration in the first reaction mixture of the Frankfurt process and have arrived at the acetic acid concentration here claimed through routine experimentation and/or so as to optimize the reaction. Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. See MPEP 2144.05.II.A.
With respect to claim 143, the Frankfurt process does not require that the molar ratio of acetic acid to sulfamic acid in the first reaction mixture ranges from 0.001:1 to 0.06:1. However, the Frankfurt process performed the process of claim 137 filed 07/17/2024, which specifies that the molar ratio of acetic acid to sulfamic acid in the first reaction mixture is less than 0.095:1. The claimed range of 0.001:1 to 0.06:1 lies inside said range of less than 0.095:1.
It would have been obvious to one of ordinary skill in the art to have varied the molar ratio of acetic acid to sulfamic acid in the first reaction mixture of the Frankfurt process and arrived at a ratio here claimed through routine experimentation and/or so as to optimize the reaction.
With respect to claim 145, the Frankfurt process performed the process of claim 137 filed 07/17/2024. The process in claim 141 uses 1 wppm (i.e., 0.0001 wt%) to 1 wt% acetic acid in the first reaction mixture. The Frankfurt process does not require acetic acid in an amount of 0.9 wt% to 1 wt% in the first reaction mixture. However, the claimed range of 0.9 wt% to 1 wt% lies inside the 0.0001-1 wt% range.
It would have been obvious to one of ordinary skill in the art to have varied the acetic acid concentration in the first reaction mixture of the Frankfurt process and arrived at the acetic acid concentration here claimed through routine experimentation and/or so as to optimize the reaction.
With respect to claim 148, the Frankfurt process performed the process of claim 147 filed 07/17/2024. The process in claim 147 sets forth that the reaction of step (a) is conducted at a temperature greater than 25°C. The Frankfurt process does not use a temperature of from 0°C to 25°C for the reaction of step (a).
It would have been obvious to one of ordinary skill in the art to have varied the temperature of reaction in step (a) of the Frankfurt process and arrived at a temperature here claimed through routine experimentation and/or so as to optimize the reaction. Generally, reaction temperature affects reaction rate. A skilled artisan desiring a slower or faster reaction can adjust the reaction temperature.
With respect to claim 154, the Frankfurt process performed the process of claim 153 filed 07/17/2024. The process in claim 153 uses a pH of from 5.9 to 6.8 for the second reaction mixture. The Frankfurt process does not use a pH in the second reaction mixture of from 6.1 to 6.4 as here claimed. The claimed pH range of 6.1 to 6.4 lies inside said pH range of from 5.9 to 6.8.
It would have been obvious to one of ordinary skill in the art to have varied the pH in the second reaction mixture of the Frankfurt process and arrived at the pH here claimed through routine experimentation and/or so as to optimize the second reaction.
With respect to claim 157, the Frankfurt process performed the process of claim 156 filed 07/17/2024, which requires, based on the total weight of second reaction mixture, 1-30 wt% diketene, 3-45 wt% amidosulfamic acid and 45-85 wt% solvent. The Frankfurt process does not have an acetic acid concentration in the second reaction mixture of less than 0.157 wt%, as here claimed.
However, acetic acid is present in the first reaction mixture in claim 156 filed 07/17/2024 in an amount of 0.0001 wt% to 1 wt%. In view of this small amount, and the fact that acetic acid is not a reactant in the second reaction mixture, it would have been obvious for one of ordinary skill in the art to have arrived at a suitable small concentration of acetic acid in the second reaction mixture, such as the concentration here claimed. This is a matter of routine experimentation and/or so as to optimize the first and second reactions.
Claim 178 is rejected under 35 U.S.C. 103 as being unpatentable over the Frankfurt process in view of admitted prior art in the ‘016 patent specification.
The Frankfurt process is relied upon as stated above in Rejection No. 1.
The Frankfurt process does not require that the second reaction mixture comprises ammonium acetate salt.
However, the ‘016 patent specification admits that in the conventional process for acesulfame potassium production, to initiate and efficiently maintain the reaction under production-scale conditions, acetic acid is added to the sulfamic acid and amine. The acetic acid may form a corresponding ammonium acetate salt, which may promote the acetoacetylation reaction that forms the acetoacetamide salt. (See col. 1, lines 20-51).
It would have been obvious to one of ordinary skill in the art to have modified the Frankfurt process such that ammonium acetate salt is formed in the first reaction mixture, because such is done in the conventional process for acesulfame potassium production, and ammonium acetate salt promotes the acetoacetylation reaction that forms acetoacetamide salt, as per the admitted conventional process in the ‘016 patent specification. As such, the ammonium acetate salt produced in the first reaction mixture carries over along with amidosulfamic acid salt produced in the first reaction mixture to the second reaction mixture.
Response to Arguments
Applicant's arguments filed November 5, 2025 have been fully considered but they are not persuasive.
Applicant’s response to the request for information under 37 CFR 1.105 is acknowledged. Applicant argues claim 137 has been amended to require that the molar ratio of amine to sulfamic acid is from 1:1 to 1.05:1, whereas the Frankfurt process used molar ratios of 1.052 or greater (Remarks, p. 8).
This argument is unpersuasive because, for the reasons set forth above in Rejection No. 1, the Frankfurt process either anticipates or renders obvious the claimed ratio.
Duty to Disclose
Applicant is reminded of the continuing obligation under 37 CFR 1.178(b), to timely apprise the Office of any prior or concurrent proceed-ing in which Patent No. 9,024,016 is or was involved. These proceedings would include interferences, reissues, reexaminations, and litigation. Applicant is further reminded of the continuing obligation under 37 CFR 1.56, to timely apprise the Office of any information which is mate-rial to patentability of the claims under consideration in this reissue appli-cation. These obligations rest with each individual associated with the filing and prosecution of this application for reissue. See also MPEP §§ 1404, 1442.01 and 1442.04.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALAN D DIAMOND whose telephone number is (571)272-1338. The examiner can normally be reached Monday through Thursday 5:30 am to 3:00 pm, and Fridays from 5:30 am to 9:30 am.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Patricia Engle can be reached on 571-272-6660. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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Signed:
/ALAN D DIAMOND/Patent Reexamination Specialist
Central Reexamination Unit 3991
Conferees:
/JOSEPH R KOSACK/Patent Reexamination Specialist
Central Reexamination Unit 3991
/Patricia L Engle/SPRS, Art Unit 3991