DETAILED ACTION
Response to Amendment
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Any new grounds of rejection set forth below are necessitated by applicant’s amendment filed on 1/16/2026. In particular, claims 1 and 15 have been amended to recite “and an absence of clay additive.” Claim 21 has been amended to remove “optionally clay.” However, it is noted that claim 21 utilizes the transitional phrase “comprises” and therefore deleting ‘optionally clay’ does not exclude clay from the aqueous slurry of claim 21.
It is noted that the newly introduced limitations were not present at the time of the preceding action. For this reason, it is proper to make the present action FINAL.
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.
Claims 1-4, 6-7, 13, 15, 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Yu et al. (US 8,323,785) in view of Bailey (US 2018/0346383). The rejection set forth in paragraphs 5-20 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference.
With regards to the amendment to claims 1 and 15, it is noted that the clay in Yu et al. is optional. See col. 15, lines 24-31. There is no disclosure of clay used in Bailey et al. Thus, it would have been obvious to one of ordinary skill in the art to produce compositions in the absence of clay as required by amended instant claims 1 and 15.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Yu et al. (US 8,323,785) in view of Bailey (US 2018/0346383) and further in view of Hemphill (US 2020/0055277).
The rejection set forth in paragraphs 5-24 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference. With regards to the amendment to claims 1 and 15, it is noted that the clay in Yu et al. (col. 15, lines 24-31) and Hemphill (¶85) is optional. There is no disclosure of clay used in Bailey et al. Thus, it would have been obvious to one of ordinary skill in the art to produce compositions in the absence of clay as required by amended instant claims 1 and 15.
Claims 9-11 are rejected under 35 U.S.C. 103 as being unpatentable over Yu et al. (US 8,323,785) in view of Bailey (US 2018/0346383) and further in view of Li (US 2016/0376191).
The rejection set forth in paragraphs 5-20 and paragraphs 25-30 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference. With regards to the amendment to claims 1 and 15, it is noted that the clay in Yu et al. is optional. See col. 15, lines 24-31. There is no disclosure of clay used in Bailey et al. Li et al. does not disclose the use of clay. Thus, it would have been obvious to one of ordinary skill in the art to produce compositions in the absence of clay as required by amended instant claims 1 and 15.
Claims 1-4, 6-15, 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Li (US 2016/0376191) in view of Bailey (US 2018/0346383). The rejection set forth in paragraphs 31-44 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference.
Neither Li nor Bailey teach the incorporation of clay which meets the amendments to claims 1 and 15.
Claims 5 are rejected under 35 U.S.C. 103 as being unpatentable over Li (US 2016/0376191) in view of Bailey (US 2018/0346383) and further in view of Hemphill (US 2020/0055277).
The rejection set forth in paragraphs 31-49 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference. Neither Li nor Bailey teach the incorporation of clay which meets the amendments to claims 1 and 15. The use of clay in Hemphill is optional. See ¶85. Thus, it would have been obvious to one of ordinary skill in the art to produce compositions in the absence of clay as required by amended instant claims 1 and 15.
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Li (US 2016/0376191) in view of Bailey (US 2018/0346383) and further in view of Yu (US 8,323,785).
The rejection set forth in paragraphs 31-44 and paragraphs 50-54 of the Non-Final rejection mailed on 10/21/2025, and any other relevant portions thereof, are incorporated herein by reference.
Neither Li nor Bailey teach the incorporation of clay which meets the amendments to claims 1 and 15. The use of clay in Yu is optional (see above). Thus, it would have been obvious to one of ordinary skill in the art to produce compositions in the absence of clay as required by amended instant claims 1 and 15.
Response to Arguments
Applicant's arguments filed 1/16/2026 have been fully considered but they are not persuasive.
The Declaration of 1/16/2026 does not provide evidence of unexpected results. MPEP 716.02(d) requires that data which is evidence of unexpected results must commensurate in scope with the claimed invention.
MPEP 716.02(d) states:
Whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the "objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support." In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. In re Clemens, 622 F.2d 1029, 1036, 206 USPQ 289, 296 (CCPA 1980).
MPEP 716.02(d), II. further states:
To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960).
The data cited to by Applicants is not commensurate in scope with the claimed invention and does not compare a sufficient number of tests inside and outside the claimed range, which is required to show unexpected results and criticality.
First, the data shows only the production of boards 5/8 in thick, where the claims recite a range of 3/8 to 1 in thick boards. For this reason alone, the data of the Declaration provided on 1/16/2026 is not commensurate in scope with the claimed invention; does not meet the requirements for showing unexpected results outlined in MPEP 716.02; and does not show persuasive evidence of unexpected results. There is no evidence showing that the allegedly unexpected results occur over the entire claimed range of thickness, which is required to show unexpected results.
Additionally, Applicant asserts, in item 9 of the Declaration, that “gypsum boards containing more than 0.5% urea are not tested as exceeding this amount would lengthen the setting time and require additional accelerator.”
This is not persuasive.
There is no evidence in support of the contention being made. Saying that a result occurs, is not evidence that it actually occurs. Furthermore, this does not meet the requirement to show a sufficient number of tests inside and outside the claimed range. The range only shows use of 0wt% as a data point outside the instantly claimed range. There are not data points above the upper end point of 0.5wt%. There is nothing indicating that use of, for example, 0.59wt% urea, does not produce an identical thermal sag, or better thermal sag, as the example as 0.5wt%. Absent any evidence, no clear conclusion can be drawn with regards to the criticality of the instantly claimed range. Applicant has not met the requirements to show unexpected results, which are outlined in MPEP 716.02, and therefore, the Declaration does not show persuasive evidence of unexpected results, and the rejections are maintained.
Furthermore, the argued result is improved thermal sag. Why wouldn’t increasing the amount of urea to an amount of, for example, 0.6wt%, give improved thermal sag, as shown by the trend in the Declaration of 1/16/2026, that increasing the amount improves thermal sag?
Item 12 of the Declaration states “The optional components in the claimed invention are not needed to achieve these unexpected results.”
This is not persuasive. There is no evidence supporting this contention. Stating something occurs, is not evidence that it occurs.
Additionally, there is nothing to support that the optional components do not affect the argued thermal sag. It is not clear how a retarder would not affect thermal sag, especially in the extremely specific amount of 8 parts by weight. Is the same thermal sag achieved when this component is excluded? If not, then the retarder, an optional component, does, in fact, affect the results which Applicants allege are unexpected, meaning the optional component would be required for the unexpected result, meaning the unexpected results do not occur over the entire claimed range. There is simply nothing proving that the contention made in item 12, i.e. nothing proving that the “optional components in the claimed invention are not needed to achieve these unexpected results.”
The dispersant and retarder of the instant claims are optional. There is nothing to indicate that when they are excluded, which falls within the scope of the instant claims, the same allegedly unexpected results will occur. What happens when these optional components, optional in the instantly claimed invention, are excluded? Are the unexpected results still achieved? There is no evidence supporting the contention that the allegedly unexpected results over the entire claimed genus, which is required to persuasively show unexpected results. It is a requirement that data must be commensurate in scope with the claimed invention in order to provide persuasive evidence of unexpected results. What this means is, that the data must show that the allegedly unexpected result occurs over the entire claimed genus and not just with specific embodiments which happen to fall within the scope of the claimed genus. As this requirement has not been met, persuasive evidence of unexpected results is not shown, and the rejections are maintained. Stating that a result occurs, is not evidence that it actually occurs.
Additionally, what is the unexpected result? What trend would be expected, and how does the instantly claimed range deviate from what’s expected, thereby providing something unexpected? Improvements do not equate to an unexpected result. No explanation of what is expected is provided, let alone how and why the instantly claimed range deviates from what’s expect. Therefore, the requirements of MPEP 716.02 are not met.
Stating that a component specifically used in the examples of the instant specification does not affect the properties, is not sufficient to demonstrate that this is factually supported as true. Evidence must be provided and not mere statements of conjecture that a component used in the compositions of the examples does not affect the properties or outcome of said examples. See paragraphs 62-67 of the Final Rejection mailed on 6/20/2025, which is incorporated herein by reference.
As articulated in the Advisory Action mailed on 9/30/2025, the Declaration filed on 9/17/2025 attempts to establish that urea is not present in the prior art. However, it is unclear how the instant invention can subject the same components to a higher temperature, and yet still have remaining urea. In Example 1 of the instant specification, the board is dried at 450ºF (232.22ºC) for 15 minutes and then 360ºF (182.22ºC) for another 15 minutes, and then 110ºF (43.33ºC) overnight. There is no indication that heating at these extremely high temperatures causes the urea present in the composition, which is added together with all the components listed in Table 2, to become the product being shown in the Declaration, i.e. that it decomposes at these temperatures. In other words, it is unclear how subjecting the instantly claimed composition, which adds urea together with stucco, which is calcium sulfate hemihydrate, and heating to temperatures well-above calcination temperatures, results in urea still being present in the instant invention but not in the prior art which heats at lower temperatures than those described in the Inventive Examples of the instant specification. This presents a potential enablement rejection.
Applicant argues on pg. 11 of the Remarks filed 1/16/2026, that if decomposition were to occur, it is irrelevant as long as the claimed invention has 0.05-0.5 wt% urea after calcination. This makes no sense, as there is no evidence, let alone data, showing that the claimed amount of urea is present after heating to the temperatures expressly disclosed in the Examples of the instant specification. The entire purpose of the Declaration of 9/17/2025, is to attempt to show that heating to a given (and random) temperature, i.e. 165ºC, causes urea to decompose. The question remains: how can the instant examples heat a composition to a temperature higher than 165ºC, which allegedly causes decomposition of urea as argued in Applicant’s own Declaration, and still have urea present, but the prior art does not? The issue is not what’s present in the claims. The issue is whether the data establishes that the prior art composition actually has no urea present, and the data does not do this. There is absolutely nothing connecting the dots or supporting the contentions that one effect at the same conditions occurs in the instant invention (heating urea at 165ºC) while a different effect at the same conditions (heating urea at 165ºC) occurs in the prior art. There is no evidence or data supporting the contentions that no urea is present in the prior art (not the hypothetical decomposition conditions of the first Declaration) but heating to even higher temperatures in the instant invention allows the urea to remain. When the urea is added is irrelevant. The Declaration of 9/17/2025 is showing that urea decomposes at 165ºC. The urea isn’t reacting. What this means is that any urea present in the Inventive Examples of the instant invention will decompose and therefore not be present as argued by Applicant’s own Declaration filed on 9/17/2025. Thus, when it is added has not been shown to have any effect on the product formed. Applicant has yet to answer the question, why would the prior art add a component, which is said to provide improvements, if that component decomposes? How would the benefits be provided if the component decomposes? The Declaration filed on 9/17/2025 is not representative of the prior art. It merely shows a hypothetical decomposition of a material (note: not complete decomposition or any specific amount of decomposition) at a random temperature. It is no way reproduces any examples from the applied prior art and thus cannot and does not show that urea decomposes in the prior art. Saying an effect occurs, is not the same as reproducing an actual example from the prior art, which is required (comparing the instant invention to the closest prior art) to show unexpected results. See MPEP 716.02.
Applicant has alleged unexpected results based on the examples in the instant specification and the data in the Declarations. However, these examples and data do not address the quantity of urea present after all the heating steps (including drying) have been performed, and thus it is not clear that the data actually corresponds to the claimed invention.
Furthermore, the requirement was that the Applicants show how the products of the prior art, namely the gypsum board products comprising the gypsum board core, differ from the instantly claimed products, when each of the instantly claimed components is present in the prior art as discussed above. The requirement is not to show that how a component used in the composition for producing the claimed gypsum board reacts when heated to a very specific and random temperature. How is the product of the prior art different, regardless of when the urea is added? The data provided by Applicants actually demonstrates that the urea of the instant claims would also not be present when reacted, because the instant specification describes even higher temperatures than those discussed in the prior art. The instant claims recite no temperature requirement-just that the components are mixed in a manner which provides a gypsum board with a gypsum core, which is disclosed in the prior art.
The gypsum boards of the prior art, particularly Yu, have identical properties discussed in the instant specification and recited in previously presented claims 13 and 14. This provides evidence that the prior art gypsum boards are, in fact, the same as the boards of the instant claims. The Declaration of 9/17/2025 shows how urea decomposes when exposed to a temperature of 165ºC. Why is this temperature being used? What happens at the higher temperatures being used in the instant specification? Why would urea not also be decomposed at those temperatures disclosed in the instant specification? Neither the new Declaration of 1/16/2026 nor the Remarks of 1/16/2026 answer this question.
The previously filed Declaration of 9/17/2025 does not provide persuasive evidence that the boards of the prior art are different than the boards of the instantly claimed invention. The data attempts to show that when stucco products with urea are exposed to temperatures of 165ºC (and therefore also higher temperatures), urea decomposes. The instantly claimed compositions, which contain urea, are exposed to temperatures higher than 165ºC, so one of ordinary skill in the art, based on the data of the Declaration, would therefore expect the urea of the instant specification to also decompose, according to Applicant’s argument and logic. This does not establish that the gypsum board products of the prior art are different than the products of the instant claims, which are also gypsum board products (and not any individual component added to the compositions of the instantly claimed invention), which are heated to temperatures above the “calcination temperature” shown the data of the Declaration.
The Declaration also raises the question, why would Bailey add a component which will simply decompose? Why add the component at all? How can the benefits of the additive be achieved if the component decomposes? Using the additives of Bailey, including 0.01 to 1wt% of urea, increases the compressive strength of gypsum cubes by up to 200% (see ¶23). How could this be true if the urea decomposes? The Declaration states that prevention of Ca(urea)4SO4 is “against Bailey’s teaching.” It is respectfully requested that Applicants cite to where there is such a teaching of prevention of formation of Ca(urea)4SO4 is present in the Bailey reference, let alone that its prevention is a requirement of Bailey. Furthermore, Bailey indicates that it is conventional to add the additives after calcination, including the additives disclosed therein, which is further evidence that adding, for example, urea, to stucco prior to calcination is conventional and was known (and therefore not unexpected) before the effective filing date of the instant invention.
Additionally, it is noted that the presence of a decomposition peak (for urea) does not mean that urea is not present. Rather, it means a quantity of urea has decomposed. For example, 10% of the urea might have decomposed, leaving 90% urea still present. This does not mean that no urea is present, which appears to be what the Declaration is contending. The peaks are not quantitative. They just show the presence of a product. Regardless, Bailey gives no indication that the urea will decompose completely which appears to be what Applicants are arguing. There can and will be urea present in the gypsum of products of Bailey, even if some may decompose (and the Examiner is not stating it will decompose).
Finally, what is the unexpected result being achieved by adding urea? Where is evidence demonstrating that said result is achieved over the entire claimed range (which is required to show unexpected results)? What property is being achieved in the instantly claimed gypsum board (note: not any method step as the elected invention is the gypsum board product) that is not being achieved in the prior art, and where is the evidence showing this? The data does not show what trend is expected, and how the entire claimed range (which is required to show unexpected results) deviates from said trend. Why does the example (Example 6) with glass fibers and urea have a higher sag resistance than the Example (Example 4) containing clay? This clearly shows addition of the optional additives (clay) can and do affect the very property which Applicant states is not affected by the optional additives (particularly the accelerator).
The data of the Declaration does not compare the instant invention with the closest prior art. The closest prior art is Yu, which expressly teaches reduction in sag resistance.
The instant specification states that the present invention provides lightweight gypsum boards with reduced thermal sag. A lightweight gypsum board with the same reduction in thermal sag is present in Yu (see above). The boards have air voids (column 24, lines 60-62). The boards of Yu have the same density and mass of pounds per area (at the same thickness) meaning they are lightweight, and specifically disclose a reduction in sag resistance (col. 19, lines 30-33; col. 33, lines 24-25). The only feature not expressly discloses is urea, which is disclosed in Bailey, as is an express rationale for the use or urea. It would have been obvious to one of ordinary skill in the art before the effective filing date of the instant invention to include from 0.01 to 1wt% of urea as disclosed in Bailey in the gypsum core and skim layers of Yu et al. in order to reduce manufacture process costs through reduction in raw materials usage and energy demand, such as by reducing the amount of water required for the gypsum slurry and heat used to dry the wallboard (see ¶8). As shown on page 9, Table II, using from 0.01 to 1wt% of urea reduces the water demand and the rate of set when used in gypsum slurries to produce gypsum board. Using the additives of Bailey, including 0.01 to 1wt% of urea, also increases the compressive strength of gypsum cubes by up to 200% (see ¶23). This could not occur if the urea were decomposed as suggested by Applicant, as this is the purpose of the additive. Applicants have not addressed this fact.
For the reasons provided above, Applicant’s arguments filed on 1/16/2026 are not persuasive. The data of the instant specification provides no evidence of criticality or unexpected results, nor does the Declaration of 1/16/2026, and thus, the rejections properly establish that the prior art provides a prima facie case of obviousness over the instantly claimed invention. The new Declaration does not establish that the prior art products are different than the instantly claimed gypsum board products. Given the totality of evidence, and particularly that the gypsum board products of the prior art have the same properties (density, thickness, mass of pounds per area for a given thickness, air voids, as well as the specific thermal insulation index values and high temperature thermal shrinkage described in the instant specification), the prior art meets the instantly claimed gypsum board. Yu et al. teaches that the panels of the invention have Thermal Insulation Index values of from about 22 minutes to about 25 minutes. See column 41, lines 10-15. Yu et al. teaches that the panels of the invention have High Temperature Shrinkage of about 2% to about 4%. These are identical to properties discussed in the instant specification and recited in previously presented instant claims 13 and 14. This is evidence that the products formed in Yu, the gypsum board products, have the same properties as the gypsum boards of the instantly claimed invention, and Applicants have provided no factually supported objective evidence that the products of Yu do not have the same properties as the instantly claimed boards. The Declaration does not compare the closest prior art, Yu, with the instantly claimed invention.
For the reasons provided above, Applicant’s arguments filed on 1/16/2026 are not persuasive.
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 K. B BOYLE whose telephone number is (571)270-7338. The examiner can normally be reached 8:30 am to 5pm, Monday - Friday.
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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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/K. BOYLE/Primary Examiner, Art Unit 1766