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 .
Election/Restrictions
Applicant’s election without traverse of Group I (i.e., claims 16-36 drawn to a process for producing terephthalic acid (TA)) in the reply filed on March 25th 2024, is acknowledged. Additionally, Applicant’s election with traverse of a species of enzyme (i.e., SEQ ID NO:1) in the electronic communication received from Applicant’s representative on September 5th 2024, is acknowledged. However, Applicants do not provide arguments for the traversal.
Status of Claims
Claims 1-15 were originally filed and amended on May 5th 2021. The amendment cancelled claims 1-15 and added new claims 16-18.
The amendment filed on 12/10/2024, amended claim 16 and cancelled claim 25.
The amendment filed on 06/25/2025, amended claims 16, 27-28 and cancelled claim 25; cancelled claims 37-38, and added new claims 39-40.
The amendment filed on 01/21/2026, amended claims 19-20, 34 and 39.
Claims 16-24, 26-36 and 39-40 are currently pending and under consideration.
Priority
The present application claims status as a 371 (National Stage) of PCT/EP2019/080277 filed November 5th 2019, and claims priority under 119(a)-(d) to French Application No. FR1860220 filed on November 6th 2018.
Receipt is acknowledged of papers submitted under 35 U.S.C. 119(a)-(d) for French Application No. FR1860220, which papers have been placed of record in the file. Please note that the application is in French and thus cannot be verified.
Sequence Interpretation
Regarding claim 32, please note that the Examiner is interpreting the scope of the enzyme capable of depolymerizing a polyester as close-ended requiring at least 75% identity with SEQ ID NO: 1 (note: elected by Applicants as the species). Since SEQ ID NO: 1 is 258 amino acids in length, a sequence that is at least 75% identical would encompass up to 64 amino acids modifications including any insertions, substitutions, deletions, etc.
Claim Interpretation
For purposes of applying prior art, the claim scope has been interpreted as set forth below per the guidance set forth at MPEP § 2111. If Applicant disputes any interpretation set forth below, Applicant is invited to unambiguously identify any alleged misinterpretations or specialized definitions in the subsequent response to the instant action. Applicant is advised that a specialized definition should be properly supported and specifically identified (see, e.g., MPEP § 2111.01(IV), describing how Applicant may act as their own lexicographer).
For claim 16, regarding the scope of “at least one enzyme capable of depolymerizing said polyester,” WO2017/198786 A1 with international publication date of November 23rd 2017 (herein after “Carbios”) teaches that the depolymerizing step is performed by contacting the plastic product with a depolymerase selected from cutinases, proteases, lipases, carboxyesterases and esterases (see Carbios, pg. 37, claim 12). Therefore an ordinary person skilled in the art would be well aware of depolymerases such as the ones previously mentioned, and would not undergo undue experimentation in order to determine which enzymes exhibit the claim function of depolymerizing a polyester. As such, given the pre-existing knowledge in the art demonstrating a representative number of species that fall within the claimed genus of an enzyme capable of depolymerizing a polyester that would exhibit the function of enzymatic depolymerization, an ordinary skilled artisan would not undergo undue experimentation to perform the claim invention with respect to the enzyme. Thus, an ordinary skilled artisan would conclude that the enablement requirement with respect to the enzyme is met.
For claim 31, regarding the scope of “a cutinase capable of depolymerizing PET,” US2005/0261465 A1 published on November 24th 2005 (herein after “Nagarajan”) teaches that hydrolytic enzymes are known in the art and include, among others, esterases, lipases, cutinases and proteases (see Nagarajan, pg. 8, para[0081]). Hydrolytic enzymes have been used to modify polyesters for: (1) the treatment of a range of organic wastes, (2) the modification of the surface of polyesters to adhere more strongly to cationic material, thereby increasing stain resistance, and (3) the hydrolysis of polyesters (see Nagarajan, pg. 8, para[0081]). Carbios also teaches that the degrading process comprises, following the amorphizing step, a step of depolymerization (see Carbios, pg. 13, lines 12-13), and contacting the plastic product with a depolymerase and/or microorganism expressing and excreting a depolymerase (see Carbios, pg. 3, lines 24-25). Advantageously, the depolymerase is selected from cutinases, lipases, proteases, carboxylesterases and esterases, preferably from cutinases and proteases (see Carbios, pg. 3, lines 25-27). The depolymerizing step targets at least one polyester targeted by the prior amorphizing step (see Carbios, pg. 13, lines 13-14). Additionally, an ordinary person skilled in the art would be well versed in what enzymes would perform the claimed function. As such, given the pre-existing knowledge in the art demonstrating a representative number of species that fall within the claimed genus of an enzyme capable of depolymerizing a polyester that would exhibit the function of enzymatic depolymerization, an ordinary skilled artisan would have put one in possession of the genus of an enzyme capable of depolymerizing a polyester. Thus an ordinary skilled artisan would conclude that the applicant was in possession of the claimed genus at the time the application was filed.
Response to Arguments
1. Applicant’s arguments, see Remarks, filed 01/21/2026, with respect to the objection to claim 39 (i.e., Duplicate Claim Warning), have been fully considered and are persuasive. The objection to claim 39, has been withdrawn.
2. Applicant’s arguments, see Remarks, filed 01/21/2026, with respect to the 35 U.S.C. 112(b) rejection, have been fully considered and are persuasive. The 35 U.S.C. 112(b) rejection of claims 19-21 and 34, has been withdrawn.
3. Applicant’s arguments, see Remarks, filed 01/21/2026, with respect to 35 U.S.C. 103 as being unpatentable over WO2015/173265 A1 with International Publication Date 19 November 2015 (herein after “Maille”) in view of US 4,355,175 Date of Patent Oct. 19, 1982 (herein after “175”); have been fully considered but are not persuasive. The 35 U.S.C. 103 rejection to claims 16-19, 21-24, 26-30, 33-35 and 39-40, has been maintained.
4. Applicant’s arguments, see Remarks, filed 01/21/2026, with respect to 35 U.S.C. 103 as being unpatentable over WO2015/173265 A1 with International Publication Date 19 November 2015 (herein after “Maille”) in further view of WO2017/198786 A1 with International Publication Date of 23 November 2017 (herein after “786”), as evidenced by Sulaiman et al., Appl Environ Microbiol. 2012, Vol. 78, No. 5, pp. 1556-1562 (herein after “Sulaiman”), GenBank., Sulaiman’s LC_Cutinase HQ704839.1 (herein after “GenBank”) and GenCore., Sequence Alignment Sulaiman's LC_Cutinase vs. Instant SEQ ID NO: 1 (herein after “GenCore”), have been fully considered but are not persuasive. The 35 U.S.C. 103 rejection to claims 16, 31-32 and 36, has been maintained.
New Claim Objections
Duplicate Claim Warning
Applicant is advised that claim 21 includes identical recitations of the claim limitations recited in claim 20; and should claim 20 be found allowable, claim 21 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
Maintained/Modified Rejections in light of Amendments
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.
103 - KSR Examples of 'Rationales' Supporting a Conclusion of Obviousness
(Consistent with the "Functional Approach" of Graham)
Further regarding 35 USC 103(a) rejections, the Supreme Court in KSR International Co. v. Teleflex Inc., 550 U.S. 398, 127 S. Ct. 1727, 82 USPQ2d 1385, 1395-97 (2007) (KSR) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper "functional approach" to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit.
Exemplary rationales that may support a conclusion of obviousness include:
(A) Combining prior art elements according to known methods to yield predictable results;
(B) Simple substitution of one known element for another to obtain predictable results;
(C) Use of known technique to improve similar devices (methods, or products) in the same way;
(D) Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results;
(E) "Obvious to try" - choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success;
(F) Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art;
(G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention.
Note that the list of rationales provided is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel.
Also, a reference is good not only for what it teaches by direct anticipation but also for what one of ordinary skill in the art might reasonably infer from the teachings. (In re Opprecht 12 USPQ 2d 1235, 1236 (Fed Cir. 1989); In re Bode 193 USPQ 12 (CCPA) 1976).
1. Claims 16-19, 21-24, 26-30, 33-35 and 39-40 are rejected under 35 U.S.C. 103 as being unpatentable over WO2015/173265 A1 with International Publication Date 19 November 2015 (herein after “Maille”) in view of US 4,355,175 Date of Patent Oct. 19, 1982 (herein after “175”).
Regarding claim 16, Maille teaches a process of recycling mixed PET plastic articles, more particularly a biological process for depolymerizing at least polyethylene terephthalate polymers of such mixed PET plastic articles and recovering resulting monomers and/or oligomers (see pg. 1, lines 1-9). Maille’s Example 1 shows the recovery of terephthalic acid and mono(2-hydroxyethyl)terephthalate by treating mixed PET plastic articles with cutinase (i.e., depolymerizing enzyme) (see pg. 22, lines 1-7); thereby constituting a process for the production of terephthalic acid from at least one polyester of interest comprising at least one TA unit comprising: a step of enzymatic depolymerization of the polyester, as recited in instant claim 16. Maille adds that mixed PET plastic articles were pre-treated to increase the surface of contact between PET and the enzyme (see pg. 25, lines 9-10); and that 10mg plastic product were incubated with 5µM cutinase, in 1mL buffer KH2PO4/K2HPO4 100 mM, pH 7.0 for 24h at 50°C with 300 rpm shaking (see pg. 25, lines 17-19). Maille also teaches that the pH of the medium may be in the range of 4 to 10, and that the pH is adjusted according to the targeted polymer/enzyme couple and the solubility of the target monomer for improving the process efficiency (see pg. 21, lines 7-9). Depolymerization of polyesters and polyamides produces acidic monomers and oligomers that induce a pH decrease; an addition of a diluted alkali can be used to compensate this acidification and maintain the pH to the optimal one (see pg. 21, lines 10-12); thereby constituting wherein the pH is regulated between 6.5 and 9 during the depolymerization step, as recited in instant claim 16. With respect to the temperature, Maille teaches that the process is implemented at a temperature comprised between 20°C and 80°C, more preferably between 25°C and 60°C; preferably, the temperature is maintained between 25°C and 50°C at least during the depolymerization step (see pg. 20, lines 23-25); thereby constituting wherein the temperature is between 35°C and 90°C during the depolymerization step, as recited in instant claim 16. Additionally, the reaction time for depolymerization of at least one polymer of the plastic article is advantageously comprised between 5 and 72 hours; such reaction time may allow the depolymerization to advance sufficiently, and will not be economically detrimental (see pg. 21, lines 27-29); thereby constituting wherein the depolymerization step is conducted for a depolymerization time between 1h and 72h, as recited in instant claim 16.
Additionally, MPEP 2144.05(I) states that "[i]n the case where the claimed ranges "overlap or lie inside ranges discloses by the prior art" a prima facie case of obviousness exists. Therefore, the claimed temperature range during the depolymerization step would have been obvious to one of ordinary skill in the art since the prior art range (i.e., 20°C and 80°C) lies within the claimed temperature range during the depolymerization step (i.e., 35°C and 90°C). Thereby, the teachings of Maille satisfy the claim limitation recited in instant claim 16, where the temperature during the depolymerization step is between 35°C and 90°C.
Maille also teaches that the time required for degradation of a mixed PET plastic article may vary depending on the mixed PET plastic article itself (i.e., nature and origin of the plastic article, its composition, shape etc.), the type and amount of microorganisms/enzymes used, as well as various process parameters (i.e., temperature, pH, additional agents, etc.) and that one skilled in the art may easily adapt the process parameters to the plastic articles and/or depolymerases (see pg. 20, lines 18-22). As such the teachings of Maille suggest a process for producing terephthalic acid (TA) from at least one polyester of interest comprising at least one TA unit comprising; a step of enzymatic depolymerization of the polyester comprising contacting the polyester with at least one enzyme capable of depolymerizing said polyester, wherein the pH is regulated between 6.5 and 9 during the depolymerization step, wherein the temperature is between 35°C and 90°C during the depolymerization step, and wherein the depolymerization step is conducted for a depolymerization time between 1h and 72h.
However, Maille does not expressly teach a stirred reactor comprising a liquid reaction medium and polyester solids as part of the depolymerization step, nor a step of recovering solubilized TA salts, nor wherein the amount of the polyester engaged in the reactor is greater than or equal to 11% by weight based on the total weight of the initial reaction medium, nor wherein the concentration of TA in the liquid phase of the final reaction medium is greater than 40 kg/t, as recited in instant claim 16.
‘175’s invention relates to an economical process for recovery of terephthalic acid (TPA) from various polyester waste materials (see column 1, lines 6-8). ‘175 describes the process in three steps as follows: in step 1, the polyethylene terephthalate (PET) scrap (chips, granules, compressed or in any convenient form) is placed into a vessel which is corrosion resistant (glass lined or hevac type) equipped with sufficient agitation and with a heater (see column 2, lines 1-6). Sufficient water and concentrated sulfuric acid in a volume ratio of 2 to 8.5-13 are added under constant mixing, at atmospheric pressure at room temperature (see column 2, lines 6-9); thereby constituting a stirred reactor comprising a liquid reaction medium as recited in instant claim 16. Within 5 to 30 minutes under constant mixing the solid waste materials (i.e., PET scrap as chips, granules, compressed or in any convenient form) will be completely liquified (depolymerized) (see column 2, lines 10-12). The depolymerized waste materials are then diluted with an equal volume of cold water and the diluted liquid is then rapidly filtered (see column 2, lines 12-14). The solid material is collected in the filter, the liquid material (ethylene glycol, water, excess acid and some impurities) is discarded (waste disposal) (see column 2, lines 15-18); thereby constituting a liquid reaction medium and polyester solids as part of the depolymerization step as recited in instant claim 16.
‘175 teaches that in step 2, the collected solids containing the TPA and impurities, are suspended in water in a convenient tank at room temperature, then treated with potassium, ammonium or sodium hydroxide, to raise the pH to 6 to 13 (see column 2, lines 20-23). In this step the TPA will dissolve and the impurities will be precipitated (see column 2, lines 23-25). ‘175 adds that treating the crude terephthalic acid with water and a base selected from the group consisting of potassium hydroxide, sodium hydroxide and ammonium hydroxide forms a solution of a water-soluble salt of the acid and filtering the solution to remove solid impurities (see column 7, claim 1, steps (c) and (d), lines 19-25); thereby constituting recovering solubilized TA salts as recited in instant claims 16.
‘175 also teaches Example 8, which describes that a previously used polyester beverage bottle was separated from the metal cap and the polyethylene reinforcement bottom part and crushed (see column 6, lines 27-31). 100 g of the crushed scrap was put into a container which contained 25ml of water and 130 ml concentrated sulfuric acid and under constant mixing at room temperature the material was depolymerized within 10 minutes (see column 6, lines 34-37). The Examiner notes that the total weight of the initial reaction medium in ‘175’s Example 8 is 364g calculated by converting the volume of liquid to grams for both water and sulfuric acid (i.e., 130ml of sulfuric acid is equivalent to 239g, and 25ml of water is equivalent to 25g), and adding 100g of crushed bottle. Therefore, the percentage of the part weight relative to the total weight for Example 8 is calculated by dividing 100g of crushed bottled (i.e., part weight) over 364g of total weight x 100 resulting in 27%. Therefore, the amount of polyester engaged in ‘175’s reactor (i.e., in Example 8) is greater than 11%. As such, the teachings of ‘175 suggest wherein the amount of the polyester engaged in the reactor is greater than or equal to 11% by weight based on the total weight of the initial reaction medium as recited in instant claim 16.
With respect to wherein the concentration of TA in the liquid phase of the final reaction medium is greater than 40 kg/t, as recited in instant claim 16:
‘175 teaches several examples where the obtained percent yield of terephthalic acid was 82.56% (see Example 2, column 4, lines 21-52), 82.97% (see Example 6, column 5, lines 50-21), 84.35% (see Example 7b, column 6, lines 21). However, ‘175 does not expressly teach the concentration of TA in the liquid phase of the final reaction medium. Since the teachings of Maille when combined with the teachings of ‘175 render each of the claim manipulative steps obvious (i.e., the depolymerization step with the enzyme, the recovering step of solubilized TA salts, the amount of polyester engaged in the reactor being greater than 11% by weight of the initial reaction medium, the pH regulated between 6.5 and 9, the temperature between 35°C and 90°C, and the depolymerization time). Taking into consideration the instant specification which teaches that the claimed process makes it possible to obtain at the conclusion of the depolymerization step a terephthalic acid concentration of at least 40 kg/t based on the total weight of the liquid phase of the final reaction medium (see instant specification, pg. 14, lines 11-13); and that the depolymerization step is considered to have been completed when the depolymerization rate of the polyester of interest reaches at least 80%, preferentially at least 90% (see instant specification, pg. 14, lines 14-15). Additionally, since claims are given their broadest reasonable interpretation in light of the supporting disclosure; and the disclosure may be express, implicit, or inherent as stated in MPEP 2103(I)C. The percent yield of terephthalic acid obtained by ‘175 in Examples 2, 6, and 7 (i.e., 82.56% , 82.97%, 84.35%, respectively) can be correlated to a depolymerization rate of at least 80% or completion of the depolymerization step. Thus, necessarily resulting in the concentration of TA in the liquid phase of the final reaction medium to be greater than 40 kg/t. Therefore the combination of references renders all claim manipulative steps parameters obvious because a person of ordinary skill in the art would have expected to obtain 40kg/t or more of TP acid in the liquid phase of the final reaction medium.
Additionally, MPEP 2112-2112.02 states that when a reference discloses all the limitations of a claim except for a property or function, and the Examiner cannot determine whether or not the reference inherently possesses properties which anticipate or render obvious the claimed invention but has basis for shifting the burden of proof to applicant as in In re Fitzgerald, 619 F.2d 67, 205 USPQ 594 (CCPA 1980). In the instant case, ‘175 teaches a process for recovery of terephthalic acid from various polyester waste materials where the obtained percent yield was at least 80% (i.e., 82.56%, 82.97%, 84.35%). The Patent and Trademark Office is not equipped to conduct experimentation in order to determine whether or not the concentration of TA in the liquid phase of the final reaction medium is greater than 40kg/t. The cited art taken as a whole demonstrates a reasonable probability the concentration of TA in the liquid phase of the final reaction medium is either identical or sufficiently similar to the claimed 40 kg/t and that whatever differences exists are not patentably significant. Thus, with the showing of the reference, the burden of establishing novelty or non-obviousness by objective evidence is shifted to the Applicants. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, because the combined teachings of the prior art are fairly suggestive of the claimed invention.
From the teachings of the references, the Examiner recognizes that it would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the biological process for depolymerizing at least polyethylene terephthalate polymers of mixed PET plastic articles and recovering resulting monomers and/or oligomers of Maille with the teachings of ‘175 in order to arrive at the claimed process for producing terephthalic acid comprising a stirred reactor comprising a liquid reaction medium and polyester solids as part of the depolymerization step, comprising the step of recovering solubilized TA salts, comprising wherein the amount of the polyester engaged in the reactor is greater than or equal to 11% by weight based on the total weight of the initial reaction medium, and comprising wherein the concentration of TA in the liquid phase of the final reaction medium is greater than 40 kg/t.
One of ordinary skill in the art before the effective filing date of the claimed invention would have been motivated to do so because it was known that treating collected solids containing terephthalic acid and impurities following a depolymerization step (i.e., crude terephthalic acid) with water and a base selected from the potassium hydroxide, sodium hydroxide and ammonium hydroxide forms a solution of a water-soluble salt of the acid, thus dissolving the terephthalic acid and precipitating any impurities as taught by ‘175. One of ordinary skill in the art before the effective filing date of the claimed invention would have had a reasonable expectation of success given that the process for recovering terephthalic acid from various polyester waste materials of ‘175 was economical; given that the process included initial amounts of polyester greater than 11% by weight based on the total weight of the initial reaction medium; and given that final percent yield of terephthalic acid obtained after the three step process was at least 80% as demonstrated by ‘175. Therefore, a biological process for depolymerizing mixed PET plastic articles and recovering resulting monomers (i.e., terephthalic acid) from the depolymerization step as taught by Maille; by applying water and a base selected from the group consisting of potassium hydroxide, sodium hydroxide and ammonium hydroxide to form a solution of a water-soluble salt of the acid wherein the final yield of TA is at least 80% as taught by ‘175, would support a process for producing terephthalic acid (TA) from at least one polyester of interest comprising: a stirred reactor comprising a liquid reaction medium and polyester solids as part of the depolymerization step; a step of recovering solubilized TA salts; wherein the amount of the polyester engaged in the reactor is greater than or equal to 11% by weight based on the total weight of the initial reaction medium; and wherein the concentration of TA in the liquid phase of the final reaction medium is greater than 40 kg/t, by constituting some teaching, suggestion or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention; and/or the use of a known technique to improve similar devices (methods, or products) in the same way; and/or the application of a known technique to a known device (method, or product) ready for improvement to yield predictable results pursuant to KSR.
Regarding claim 17, Maille teaches that the added amount of enzyme for the depolymerization step is at most 5% by weight of plastic articles, preferably at most 1 %, more preferably at most 0.1 %, and even more preferably at 60 most 0.05% (see pg. 21, lines 1-3). Advantageously, the added amount of degradation enzyme is in a range of 0.001 % to 5% by weight of plastic article, preferably in a range of 0.001 % to 1 %, more preferably in a range of 0.001 % to 0.1 %, even more preferably in a range of 0.001 % to 0.05% (see pg. 21, lines 3-6). Maille adds that one skill in the art may easily adapt the process parameters (i.e., type and amount of microorganism/enzymes used, temperature, pH, additional agents, etc.) to the plastic articles and/or depolymerases (see pg. 20, lines 20-22). Additionally, with respect to process parameters, it is noted that Maille teaches the amount of enzyme by weight of plastic articles added for the depolymerization step. The ratio by weight of the amount of enzyme engaged to the amount of polyester of interest engaged is clearly a result specific parameter that a person of ordinary skill in the art would routinely optimize. Optimization of parameters is a routine practice that would be obvious for a person of ordinary skill in the art to employ. It would have been customary for an artisan of ordinary skill to determine the optimal ratio of amount of enzyme to amount of polyester of interest needed to achieve the desired results. Thus, an ordinary skilled artisan would have been motivated to modify the range amount of degradation enzyme by weight of plastic article as taught by Maille in the depolymerization step of mixed PET plastic articles, because an ordinary skilled artisan would have been able to utilize the teachings of Maille to obtain various process parameters with a reasonable expectation of success. Thus, absent some demonstration of unexpected results from the claimed parameters, the optimization of the ratio by weight of the amount of enzyme engaged to the amount of polyester of interest engaged would have been obvious at the time of applicant's invention. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, because the combined teachings of the prior art are fairly suggestive of the claimed invention.
Regarding claim 18, Maille teaches that the mixed PET plastic article may contain an additional polyester, preferably selected from polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polyethylene isosorbide terephthalate (PEIT), polybutylene adipate terephthalate (PBAT), polycyclohexylenedimethylene terephthalate (PCT), polyethylene terephthalate glycol-modified (PETO), and blends/mixtures of these materials (see pg. 5, lines 28-29; pg. 8, lines 26-28 and pg. 9, line 10); thereby constituting the claim limitations recited in instant claim 18.
Regarding claims 19-21, ‘175 teaches several Examples where the amount of polyester engaged in the reactor is greater than 11%, in particular Example 8, which 100 g of the crushed scrap was put into a container which contained 25ml of water and 130 ml concentrated sulfuric acid and under constant mixing at room temperature the material was depolymerized within 10 minutes (see column 6, lines 34-37). The Examiner notes that the total weight of the initial reaction medium in ‘175’s Example 8 is 364g calculated by converting the volume of liquid to grams for both water and sulfuric acid (i.e., 130ml of sulfuric acid is equivalent to 239g, and 25ml of water is equivalent to 25g), and adding 100g of crushed bottle. Therefore, the percentage of the part weight relative to the total weight for Example 8 is calculated by dividing 100g of crushed bottled (i.e., part weight) over 364g of total weight x 100 resulting in 27%. Additionally, a prima facie case of obviousness exists where the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have the same properties. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%). See MPEP 2144.05(I). Therefore, the claimed amount of polyester engaged in the reactor is comprised between 11% and 20% by weight based on the total weight of the initial reaction medium, as recited in instant claim 19; the claimed amount of polyester engaged in the reactor is equal to 15% by weight based on the total weight of the initial reaction medium, as recited in instant claim 20; and the claimed amount of polyester engaged in the reactor is greater than or equal to 15% by weight based on the total weight of the initial reaction medium, as recited in instant claim 21 would have been suggested to one skilled in the art.
Regarding claim 22, as previously mentioned, MPEP 2112-2112.02 states that when a reference discloses all the limitations of a claim except for a property or function, and the Examiner cannot determine whether or not the reference inherently possesses properties which anticipate or render obvious the claimed invention but has basis for shifting the burden of proof to applicant as in In re Fitzgerald, 619 F.2d 67, 205 USPQ 594 (CCPA 1980). In the instant case, ‘175 teaches a process for recovery of terephthalic acid from various polyester waste materials where the obtained percent yield was at least 80% (See ‘175’s Examples 2 (82.56%), Example 6 (82.97%), and Example 7 (84.35%)). Taking into consideration the instant specification which teaches that the claimed process makes it possible to obtain at the conclusion of the depolymerization step a terephthalic acid concentration of at least 40 kg/t based on the total weight of the liquid phase of the final reaction medium (see instant specification, pg. 14, lines 11-13); and that the depolymerization step is considered to have been completed when the depolymerization rate of the polyester of interest reaches at least 80%, preferentially at least 90% (see instant specification, pg. 14, lines 14-15); and since MPEP 2103(I)C states that claims are given their broadest reasonable interpretation in light of the supporting disclosure; and the disclosure may be express, implicit, or inherent as stated in. The percent yield of terephthalic acid obtained by ‘175 in Examples 2, 6, and 7 can be correlated to a depolymerization rate of at least 80% or completion of the depolymerization step. Thus, necessarily resulting in the concentration of TA in the liquid phase of the final reaction medium to be greater than 40 kg/t. Additionally, The Patent and Trademark Office is not equipped to conduct experimentation in order to determine whether or not the concentration of TA in the liquid phase of the final reaction medium is greater than 50kg/t, 60kg/t, 70kg/t, 80kg/t, 100kg/t or 120kg/t. The cited art taken as a whole demonstrates a reasonable probability that the concentration of TA in the liquid phase of the final reaction medium is either identical or sufficiently similar to the claimed 50kg/t, 60kg/t, 70kg/t, 80kg/t, 100kg/t or 120kg/t and that whatever differences exists are not patentably significant. Thus, with the showing of the reference, the burden of establishing novelty or non-obviousness by objective evidence is shifted to the Applicants. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, because the combined teachings of the prior art are fairly suggestive of the claimed invention.
Regarding claim 23, Maille teaches that the mixed PET plastic article may be transformed to an emulsion or a powder, which is added to a liquid medium containing the microorganisms and/or enzymes (see pg. 20, lines 2-4); thereby constituting wherein the polyester of interest is in powder form, as recited in instant claim 23.
Regarding claim 24, Maille teaches that the pH of the medium may be in the range of 4 to 10 (see pg. 21, line 7). Advantageously, the pH is adjusted according to the targeted polymer/enzyme couple and the solubility of the targeted monomer for improving the process efficiency (see pg. 21, lines 7-9). More particularly, the pH is adjusted to be maintained at the optimal pH of the enzyme. Indeed, depolymerization of polyesters and polyamides produces acidic monomers and oligomers that induce a pH decrease (see pg. 21, lines 9-11). An addition of a diluted alkali can be used to compensate this acidification and maintain the pH to the optimal one (see pg. 21, lines 11-12). Additionally, the MPEP 2144.05(I) states that "[i]n the case where the claimed ranges "overlap or lie inside ranges discloses by the prior art" a prima facie case of obviousness exists. Therefore, the claimed pH during the depolymerization step would have been obvious to one of ordinary skill in the art since the prior art range (i.e., the pH of the medium may be in the range of 4 to 10) lies within the claimed regulated pH range (i.e., between 6.5 and 8.5).
Regarding claim 26, ‘175 teaches that in step 2, the collected solids containing the TPA and impurities, are suspended in water in a convenient tank at room temperature, then treated with potassium, ammonium or sodium hydroxide, to raise the pH to 6 to 13 (see column 2, lines 20-23). In this step the TPA will dissolve and the impurities will be precipitated (see column 2, lines 23-25). ‘175 adds that treating the crude terephthalic acid with water and a base selected from the group consisting of potassium hydroxide, sodium hydroxide and ammonium hydroxide forms a solution of a water-soluble salt of the acid and filtering the solution to remove solid impurities (see column 7, claim 1, steps (c) and (d), lines 19-25). Thereby constituting wherein the step of recovering the solubilized TA salts comprises the step of separating the liquid phase containing the TA salts from the remaining reaction medium, as recited in instant claim 26.
Regarding claim 27, ‘175 teaches acidifying the filtrate (i.e., the solution of a water-soluble salt of the acid) with acid to form a precipitate of purified terephthalic acid (see column 7, claim 1, lines 26-27); thereby constituting wherein the process further comprises recovering the TA by precipitating the TA contained in the TA salts, as recited in instant claim 27.
Regarding claims 28-29, ‘175 teaches that the obtained solution is then acidified with diluted or concentrated sulfuric acid to a pH of 0-2 to cause precipitation of TPA (see column 2, lines 37-39); thereby constituting wherein the process comprises the step of separating the TA salts, and a step of recovering the TA by precipitation, as recited in instant claim 28; and constituting wherein precipitation of TA is achieved by acidification of the medium, as recited in instant claim 29.
Regarding claims 30 and 40, ‘175 teaches that after filtration to remove the fine precipitate, the residue (undissolved scrap material, if any, and impurities) is discarded as solid waste (see column 2, lines 31-33) The liquid is then collected and must be clear, although it may be light brownish in color (if dark colored, it must be treated with activated charcoal and refiltered from the charcoal) (see column 2, lines 33-37); thereby constituting wherein the purification step is performed by decolorization on carbon, as recited in instant claims 30 and 40.
Regarding claim 33, Maille teaches that the pH is adjusted according to the targeted polymer/enzyme couple and the solubility of the targeted monomer for improving the process efficiency. More particularly, the pH of the medium is adjusted to be maintained at the optimal pH of the enzyme. Indeed depolymerization of polyesters produces acidic monomers and oligomers that induce a pH decrease. An addition of a diluted alkali can be used to compensate this acidification and maintain the pH to the optimal one (see pg. 21, lines 7-12). Maille reiterates that one skilled in the art may easily adapt the process parameters to the plastic articles and/or depolymerases by adjusting various process parameters such as temperature, pH, the nature and origin of the plastic article, its composition, its shape and/or the type and amount of enzymes used (see pg. 20, lines 18-22).
Additionally, as previously mentioned, regulating the pH during the depolymerization step by the addition to the reaction medium of a basic solution concentrated to at least 10% ± 1%, by weight of the base based on the total weight of the basic solution, is clearly a result specific parameter that a person of ordinary skill in the art would routinely optimize. Optimization of parameters is a routine practice that would be obvious for a person of ordinary skill in the art to employ. It would have been customary for an artisan of ordinary skill to determine the optimal concentration by weight of base based on the total weight of the basic solution needed to achieve the desired results. Thus, an ordinary skilled artisan would have been motivated to modify the process parameters such as the concentration of a diluted alkali solution used to compensate the acidification produced by the depolymerization of polyesters and maintain an optimal pH as taught by Maille; because an ordinary skilled artisan would have been able to utilize the teachings of Maille to regulate the pH during the depolymerization process with a reasonable expectation of success. Thus, absent some demonstration of unexpected results from the claimed parameters, the optimization of the pH by the addition of a basic solution concentrated to at least 10% ± 1% by weight of base based on the total weight of the basic solution would have been prima facie obvious before the effective filing date of Applicant's invention. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art at the time the invention was made, because the combined teachings of the prior art are fairly suggestive of the claimed invention.
Regarding claim 34, as previously discussed, ‘175 teaches Example 8, wherein 100g of a crushed polyester beverage bottle were depolymerized with 25ml of water and 130 ml of concentrated sulfuric acid under constant mixing (see column 6, lines 34-37). The Examiner notes that the total weight of the initial reaction medium in ‘175’s Example 8 is 364g calculated by converting the volume of liquid to grams for both water and sulfuric acid (i.e., 130ml of sulfuric acid is equivalent to 239g, and 25ml of water is equivalent to 25g), and adding 100g of crushed bottle. Therefore, the percentage of the part weight relative to the total weight for Example 8 is calculated by dividing 100g of crushed bottled (i.e., part weight) over 364g of total weight x 100 resulting in 27%. Therefore, the amount of polyester engaged in ‘175’s reactor (i.e., in Example 8) is greater than 11%. Additionally, a prima facie case of obviousness exists where the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have the same properties. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%). See MPEP 2144.05(I). Therefore, the claimed amount of polyester engaged in the reactor (i.e., between 15% and 25% by weight, based on the total weight of the initial reaction medium), as recited in instant claim 34 would have been suggested to one skilled in the art.
With respect to wherein the pH is regulated between 7.5 and 8.5 during the depolymerization step by the addition to the reaction medium of a basic solution concentrated to at least 15% ± 1%:
As previously discussed, Maille teaches that the pH of the medium may be in the range of 4 to 10 (see pg. 21, line 7). Advantageously, the pH is adjusted according to the targeted polymer/enzyme couple and the solubility of the targeted monomer for improving the process efficiency (see pg. 21, lines 7-9). More particularly, the pH is adjusted to be maintained at the optimal pH of the enzyme. Indeed, depolymerization of polyesters and polyamides produces acidic monomers and oligomers that induce a pH decrease (see pg. 21, lines 9-11). An addition of a diluted alkali can be used to compensate this acidification and maintain the pH to the optimal one (see pg. 21, lines 11-12). Additionally, the MPEP 2144.05(I) states that "[i]n the case where the claimed ranges "overlap or lie inside ranges discloses by the prior art" a prima facie case of obviousness exists. Therefore, the claimed pH during the depolymerization step would have been obvious to one of ordinary skill in the art since the prior art range (i.e., the pH of the medium may be in the range of 4 to 10) lies within the claimed regulated pH range (i.e., between 7.5 and 8.5).
With respect to wherein the concentration of TA in the liquid phase of the final reaction medium is greater than 100 kg/t:
As previously discussed, the Patent and Trademark Office is not equipped to conduct experimentation in order to determine whether or not the concentration of TA in the liquid phase of the final reaction medium is greater than 100kg/t. The cited art taken as a whole demonstrates a reasonable probability that the concentration of TA in the liquid phase of the final reaction medium is either identical or sufficiently similar to the claimed 100kg/t and that whatever differences exists are not patentably significant. Therefore, with the showing of the references, the burden of establishing novelty or non-obviousness by objective evidence is shifted to the Applicants. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, because the combined teachings of the prior art are fairly suggestive of the claimed invention. As such, the combination of references suggest the claim limitations as recited in instant claim 34.
Regarding claim 35, Maille teaches that the process is implemented at a temperature comprised between 20°C and 80°C (see pg. 20, lines 23-24). Additionally, the MPEP 2144.05(I) states that "[i]n the case where the claimed ranges "overlap or lie inside ranges discloses by the prior art" a prima facie case of obviousness exists. Therefore, the claimed temperature range would have been obvious to one of ordinary skill in the art since the prior art range (i.e., 20°C and 80°C) lies within the claimed temperature range (i.e., 60°C and 80°C).
Regarding claim 39, as previously mentioned, ‘175 teaches that in step 2, the collected solids containing the TPA and impurities, are suspended in water in a convenient tank at room temperature, then treated with potassium, ammonium or sodium hydroxide, to raise the pH to 6 to 13 (see column 2, lines 20-23). In this step the TPA will dissolve and the impurities will be precipitated (see column 2, lines 23-25). Thereby constituting separating the TA salts from the liquid reaction medium to form a final reaction medium liquid phase, said liquid phase being free of solid and/or suspended polyester particles, concentrating TA by removing water from the liquid phase and precipitating the TA salts; recovering the precipitated TA salts and resolubilizing the precipitated TA salts into a solution; as recited in instant claim 39. ‘175 adds that the obtained solution is then acidified with diluted or concentrated sulfuric acid to a pH of 0-2 to cause precipitation of TPA (see column 2, lines 37-39). Thereby constituting acidifying the resolubilized TA salt solution to precipitate TA, as recited in instant claim 39. ‘175 also teaches that the TPA is filtered and washed with water until acid-and salt-free (see column 2, lines 42-43). Thus, the teachings of Maille when combined with the teachings of ‘175 are suggestive of the claim limitations recited in instant claims 16-19, 21-24, 26-30, 33-35 and 39-40.
2. Claims 16, 31-32 and 36 are rejected under 35 U.S.C. 103 as being unpatentable over WO2015/173265 A1 with International Publication Date of 19 November 2015 (herein after “Maille”) for claim 16 above, and in further view of WO2017/198786 A1 with International Publication Date of 23 November 2017 (herein after “786”), as evidenced by Sulaiman et al., Appl Environ Microbiol. 2012, Vol. 78, No. 5, pp. 1556-1562 (herein after “Sulaiman”), GenBank., Sulaiman’s LC_Cutinase HQ704839.1 (herein after “GenBank”) and GenCore., Sequence Alignment Sulaiman's LC_Cutinase vs. Instant SEQ ID NO: 1 (herein after “GenCore”) for claims 31-32 and 36 herewith.
The teachings of Maille with respect to claim 16 are discussed above.
Regarding claims 31 and 32, Maille teaches Example 2, which shows the recovery of terephthalic acid by treating a PET bottle containing PET and additives with the cutinase ThcCutl from Thermobifida cellulosilytica DSM 44535 (see pg. 27, lines 15-17). However, Maille does not expressly teach wherein the enzyme is selected from enzymes having an amino acid sequence having at least 75% identity with SEQ ID NO: 1.
‘786 teaches a process for degrading plastic products comprising polyethylene terephthalate and/or polylactic acid, the process comprises a depolymerization step (see Abstract). ‘786 teaches that the enzymatic depolarization of the samples was performed with a LC-cutinase produced from recombinant expression in Escherichia coli as per the findings of Sulaiman. Additionally, Sulaiman evidences accession number HQ704839 deposited in GenBank for the nucleotide sequence of the LC-cutinase (see GenBank). Upon comparing translated nucleotide sequence of HQ704839 to instant SEQ ID NO: 1, it is noted that the amino acid sequence corresponding to HQ704839 is 100% identical to SEQ ID NO: 1 (see GenCore).
The Examiner notes that one of ordinary skill in the art would look into the teachings of ‘786 to select a cutinase enzyme having an amino acid sequence at least 75% identical to instant SEQ ID NO: 1 because ‘786 teaches the enzymatic depolarization of the samples was performed with a LC-cutinase produced from recombinant expression in Escherichia coli as per the findings of Sulaiman. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Maille with the teachings of ‘786 to enzymatically depolarize the PET samples. One of ordinary skill in the art would have been motivated and would have had a reasonable expectation of success given that Maille’s method of producing monomers and/or oligomers from a mixed PET plastic article comprises hydrolyzing the PET bottle with the cutinase Thc_Cutl; and given that the LC-cutinase used by ‘786 is 100% identical to instant SEQ ID NO: 1. As such, one of ordinary skill in the art would be motivated to apply a known technique to a known method ready for improvement to yield predictable results and/or use of known technique to improve similar devices (methods, or products) in the same way. Accordingly, the teachings of Maille when combined with the teachings of ‘786 render claims 31-32 and 36 obvious.
Regarding claim 36, Maille’s Example 1 teaches hydrolysis of mixed PET plastic articles where the plastic product was incubated with the cutinase in buffer, pH 7.0 for 24h at 50°C with 300 rpm shaking (see pg. 25, lines 17-19). After the enzymatic treatment, proteins were precipitated and furthered process and TA analyzed (see pg. 25, last paragraph). However, Maille does not expressly teach wherein the process is carried out in a reactor whose volume is greater than 1000L as recited in instant claim 36.
‘786 teaches enzymatic depolymerization of amorphized water bottles in a reactor (see pg. 32, line 16). Where two Minibio 500 reactors were started with 10g of samples and 100 ml of 10 mM potassium phosphate buffer pH 8 containing 10 mg of LC-cutinase. Agitation was set at 250 rpm using a marine impeller. The bioreactors were thermostated at 65°C by immersing them in an external water bath; pH was regulated at 8 by addition of KOH at 3 M and the different parameters (pH, temperature, agitation, addition of base) were monitored (see pg. 32, lines 17-22).
The Examiner notes that one of ordinary skill in the art would look into the teachings of ‘786 to carry out the process in a 1000L bioreactor because ‘786 teaches the enzymatic depolarization of the amorphized water bottles in two 500L bioreactors. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Maille with the teachings of ‘786 and process 1000L of medium comprising at least one polyester of interest and at least one depolymerizing enzyme to produce terephthalic acid. One of ordinary skill in the art would have been motivated and would have had a reasonable expectation of success given that Maille’s method of producing monomers and/or oligomers from a mixed PET plastic article comprises hydrolyzing the PET bottle with the cutinase in buffer, pH 7.0 for 24h at 50°C with 300 rpm shaking; and given that amorphized water bottles were depolymerized in a reactor as taught by ‘786. As such, one of ordinary skill in the art would be motivated to apply a known technique to a known method ready for improvement to yield predictable results and/or use of known technique to improve similar devices (methods, or products) in the same way. Accordingly, the teachings of Maille when combined with the teachings of ‘786 render claim 35 obvious.
From the teachings of the references, it is apparent that one of ordinary skill in the art would have had a reasonable expectation of success in producing the claimed invention. Therefore, the invention as a whole was prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
Response to Arguments
Applicant’s arguments filed on 01/21/2026, with respect to claims 16-24, 26-36 and 39-40, have been considered but are not persuasive for the following reasons:
It is reiterated that there is not a single reference that teaches and/or suggests every claim limitation recited in instant claim 16 and the dependent claims. However, Applicant is respectfully reminded that the rejections supra are based on obviousness. Pursuant to MPEP 2142, 35 USC 103 authorizes a rejection where, to meet the claim, it is necessary to modify a single reference or to combine it with one or more other references (emphasis added). Since the rejection is based on obviousness, it is unnecessary for every claim limitation to be taught and/or suggested by a single reference. Additionally, the Examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
In this case, as discussed above in the 35 U.S.C. 103 rejection, Maille teaches a biological process for depolymerizing at least polyethylene terephthalate polymers of mixed PET plastic articles and recovering resulting monomers and/or oligomers. Pusztaszeri (i.e., ‘175) teaches recovery of terephthalic acid (TPA) from various polyester waste materials; and Desrousseaux (i.e., ‘786) teaches a process for degrading plastic products comprising polyethylene terephthalate and/or polylactic acid, the process comprises a depolymerization step which includes LC-cutinase which is 100% identical to instant SEQ ID NO: 1.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Maille with the teachings of ‘786 to enzymatically depolarize the PET samples. One of ordinary skill in the art would have been motivated and would have had a reasonable expectation of success given that Maille’s method of producing monomers and/or oligomers from a mixed PET plastic article comprises hydrolyzing the PET bottle with the cutinase Thc_Cutl; and given that the LC-cutinase used by ‘786 is 100% identical to instant SEQ ID NO: 1. One of ordinary skill in the art would also have been motivated combine the teachings of Maille and ‘175 to arrive at the claim process, because before the effective filing date of the claimed invention it was known that terephthalic acid could be depolymerized (enzymatically and/or chemically); because it was also known that the process for recovering terephthalic acid from various polyester waste materials was economical; because the process included initial amounts of polyester greater than 11% by weight, based on the total weight of the initial reaction medium; and because the final percent yield of terephthalic acid obtained after the three step process of ‘175 was at least 80%.
As such one of ordinary skill in the art would be motivated to apply a known technique (i.e., enzymatic depolymerization with LC-cutinase) to a known method (i.e., enzymatically and/or chemically terephthalic acid depolymerization) ready for improvement to yield predictable results and/or use of known technique to improve similar devices (methods, or products) in the same way.
With respect to Applicant’s assertion that none of the cited documents describes or suggests using an initial amount of polyester of at least 11 wt% for enzymatic depolymerization (see Remarks, filed 01/21/2026, pg. 8, third paragraph). The ratio by weight of the amount of enzyme engaged to the amount of polyester of interest engaged is clearly a result specific parameter that a person of ordinary skill in the art would routinely optimize. Optimization of parameters is a routine practice that would be obvious for a person of ordinary skill in the art to employ. It would have been customary for an artisan of ordinary skill to determine the optimal ratio of amount of enzyme to amount of polyester of interest needed to achieve the desired results. Thus, an ordinary skilled artisan would have been motivated to modify the range amount of degradation enzyme by weight of plastic article as taught by Maille in the depolymerization step of mixed PET plastic articles, because an ordinary skilled artisan would have been able to utilize the teachings of Maille to obtain various process parameters with a reasonable expectation of success. Thus, absent some demonstration of unexpected results from the claimed parameters, the optimization of the ratio by weight of the amount of enzyme engaged to the amount of polyester of interest engaged would have been obvious at the time of applicant's invention. Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, because the combined teachings of the prior art are fairly suggestive of the claimed invention.
With respect to Applicant’s assertion that one skilled in the art would not have expected to recover terephthalic acid as solubilized salts at the end of the enzymatic depolymerization in view of the teachings of the cited references (see Remarks, filed 01/21/2026, pg. 8, last paragraph), has been considered but it is not persuasive.
It is the Examiner’s understanding that Applicant’s statements amount to a suggestion that the prior art is not fully enabled or operable. Pursuant to MPEP 2121(I), when the reference relied on expressly anticipates or makes obvious all the elements of the claimed invention, the reference is presumed to be operable. Once such a reference is found, the burden is on applicant to rebut the presumption of operability. In re Sasse, 629 F.2d 675, 207 USPQ 107 (CCPA 1980). Moreover, MPEP 2121(III) states that a prior art reference provides an enabling disclosure and thus anticipates a claimed invention if the reference describes the claimed invention in sufficient detail to enable a person of ordinary skill in the art to carry out the claimed invention; "proof of efficacy is not required for a prior art reference to be enabling for purposes of anticipation." Impax Labs. Inc. v. Aventis Pharm. Inc., 468 F.3d 1366, 1383, 81 USPQ2d 1001, 1013 (Fed. Cir. 2006). MPEP 716.07 states that since in a patent it is presumed that a process if used by one skilled in the art will produce the product or result described therein, such presumption is not overcome by a mere showing that it is possible to operate within the disclosure without obtaining the alleged product. In re Weber, 405 F.2d 1403, 160 USPQ 549 (CCPA 1969).
Therefore Applicants are suggesting that the existence of multiple alternative combinations of methods to depolymerize polyethylene terephthalate polymers as taught by Maille, ‘175 and ‘786 is sufficient to render the claimed invention non-obvious because a person skill in the art after reading Maille would not have looked to the chemically depolymerization of PET as taught by ‘175, would not have increased the amount of engaged polyester to a value of at least 11% in the method of Maille; and would not have expected to recover terephthalic acid as solubilized salts at the end of the enzymatic depolymerization.
However merely identifying the existence of additional prior art methods usable as alternatives to depolymerize PET, does not establish lack of predictability or evidence the existence of unexpected results. MPEP §§ 2123(I)-(II) identify that the mere existence and disclosure of multiple embodiments do not constitute a “teaching away” from a broader disclosure or non-preferred embodiments (see also MPEP §§ 2143(I)). This is reasonable because if each of the alternatives merely perform an art-recognized function in the absence of any unexpected results, then the outcome remains predictable and expected, regardless of the total number of alternatives. Accordingly, the combined teachings of Maille, ‘175 and ‘786 render the claimed invention obvious, because the known enzymatically and/or chemically depolymerization methods perform a recognized function of producing terephthalic acid (TA). Therefore, an ordinary skilled artisan would have been motivated with reasonable expectation of success to combine the teachings of the prior art in order to arrive at the claimed invention.
Accordingly, the Examiner maintains that teachings of Maille when combined with the teachings of ‘175 and ‘786 render claims 16-24,26-36 and 39-40 obvious.
Conclusion
No claims are allowed.
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.
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/CLAUDIA ESPINOSA/Patent Examiner, Art Unit 1654
/LIANKO G GARYU/Supervisory Patent Examiner, Art Unit 1654