DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-20 are pending as amended on 1/16/2026.
The new grounds of rejection set forth below under 35 USC 112(b) were necessitated by Applicant’s amendment filed on 1/16/2026. Therefore, this action is properly made final.
Any rejections and/or objections made in the previous Office action and not repeated below are hereby withdrawn. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Claim Rejections - 35 USC § 112
Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites a method which produces an oligomeric PET substrate according to Formula I:
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Claim 1 is indefinite for at least the reason that the definitions of R1 and R2 recited in the two lines directly beneath the formula (I) structure:
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Are not consistent with the subsequent limitations placed on R1 and R2.
As set forth in the previous rejection under 35 USC 112(b), by defining R1 as a “carboxyl end group” or a “hydroxyl end group,” claim 1 requires one of two very specific end group structures (i.e., -COOH or -OH) to be attached on the left side of formula (I), as shown in the formulas drawn by the Examiner below:
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Similarly, by defining R2 as a “carboxyl end group” or a “hydroxyl end group” claim 1, requires one of two very specific end group structures (i.e., -COOH or -OH) to be attached on the right side of formula (I), as shown in the formulas drawn by the Examiner below:
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As previously discussed in the rejection mailed on 10/20/2025, there is no description in the specification as filed of any reactants or reactions which would result in formation hydroperoxy (HO-O) end groups, or end groups having a formula HOC(O)O-, or end groups having a formula -C(O)C(O)OH. One having ordinary skill in the art would immediately recognize that such groups (which are recognized as being explosive and/or unstable) do not result from Applicant’s disclosed reaction of BHET and terephthalic acid.
The scope of the claims is necessarily rendered unclear because an oligomeric PET according to instant Formula (I) must be produced in order for a method to meet claim 1, yet it is impossible for a method including reaction steps as presently recited and as described in the instant specification to result in a structure according to instant formula (I).
In the amendment filed on 1/16/2026, the language was added to claim 1, including:
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The language above is confusing for at least the reason that it is not possible for R1 to simultaneously be “a hydroxyl end group” (i.e., -OH) and hydrogen (i.e., “-H”). A hydroxyl end group and a hydrogen atom are not the same. Additionally, the statement “when R1 is a carboxyl end group, R1 comprises -C(O)OH” remains unclear for the same reasons previously set forth: if R1 is a carboxyl end group, the R1-O- moiety at the end of the oligomer (left side) must be:
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, which is not a group that can form as a result of Applicant’s claimed method.
The following language added to claim 1 further highlights the indefiniteness of the claimed subject matter:
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The language requires that “when R2 is a hydroxyl end group,” R2 must also somehow form a moiety -C(O)-O-R2 which comprises a hydroxyl-terminated ester group (which would require -R2 to be a hydroxyalkyl group rather than a hydroxyl group). It is impossible for -R2 to simultaneously be hydroxyl (-OH) and hydroxyalkyl, yet this appears to be required by the claim. Similarly, the claim requires that “when R2 is a carboxyl end group, R2 is -OH…” It is impossible for R2 to simultaneously be carboxyl (-COOH) and -OH, yet this is required by the claim.
Because it is not possible to determine what chemical structure is encompassed by instant chemical formula (I), the metes and bounds of the claimed invention (in claim 1, and dependent claims) are not clear and thus the claims are indefinite. (Claims 13 and 14 recite the same formula as in method claim 1, and therefore this rejection applies to product claims 13 and 14, and claims which depend from claims 13 and 14, for the same reasons set forth above.) Moreover, while there is reasonable basis to conclude that the claims contain one or more errors, it is not possible to determine the appropriate correction to the error(s), and therefore, it is not possible to determine a proper interpretation of the limitations of the claims. Where there is a great deal of confusion and uncertainty as to the proper interpretation of the limitations of a claim, it would not be proper to reject such a claim on the basis of prior art. As stated in In re Steele, 305 F.2d 859, 134 USPQ 292 (CCPA 1962), a rejection under 35 U.S.C. 103 should not be based on considerable speculation about the meaning of terms employed in a claim or assumptions that must be made as to the scope of the claims.
Additionally:
Claim 3 appears to require reacting rBHET with PTA (lines 1-2), but then recites an alternative set of limitations which must be satisfied when reacting the oligomeric rBHET with PTA. It is therefore not clear whether claim 3 requires reaction of rBHET with PTA. The examiner suspects Applicant intended “wherein the” in line 1 of claim 3 to be replaced with “wherein when the”.
Response to Arguments
Applicant's arguments filed 1/16/2026 have been fully considered.
Applicant argues (p 7) that the concerns raised in the rejection under 35 USC 112(b) arise from interpreting Formula I as a single isolated molecular species, while the claimed oligomeric PET substrate comprises a molecular weight distribution of oligomeric species.
The examiner understands (as explained by Applicant on p 7) that oligomers and polymers exist as mixtures containing varying chain lengths and end group compositions. However, as previously set forth in the action mailed on 10/20/2025 and as maintained in the rejection above, chemical formula (I) and the definitions of R1 and R2 contain errors. Claim 1 requires (and the specification describes) a method of reacting rBHET and PTA. A reaction of rBHET and PTA would be expected to result in a composition of oligomers having varying chain lengths and different end group combinations (e.g., a higher hydroxyl end group concentration if rBHET is in excess, or a higher carboxyl end group concentration if PTA is in excess). However, claim 1 requires production of an oligomeric PET having a structure represented by formula (I). This claim limitation cannot be disregarded or ignored, and for the reasons set forth previously and maintained above, it is impossible for any PET having a structure according to Formula (I) to result from a reaction of rBHET and PTA as is recited in the claims and as is described in the instant specification.
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 RACHEL KAHN whose telephone number is (571)270-7346. The examiner can normally be reached Monday to Friday, 8-5.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Randy Gulakowski can be reached at 571-272-1302. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/RACHEL KAHN/Primary Examiner, Art Unit 1766