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 .
This Office action is in response to the amendment filed February 25, 2026, which amends claims 1, 5, and 6. Claims 1-11 are pending.
Response to Amendment
Applicant’s amendment of the claims, filed February 25, 2026, caused the withdrawal of the rejection of claims 1, 2, and 4 under 35 U.S.C. 102(a)(1) as being anticipated by Yoon et al. (US 2019/0207123) as set forth in the Office action mailed September 30, 2025.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1, 2, and 4 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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.
Claim(s) 1, 2, and 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yoon et al. (US 2019/0207123) (hereafter “Yoon”).
Regarding clams 1, 2, and 4, Yoon teaches an electroluminescent device comprising an organic electroluminescent compound (paragraphs [0105]-[0128]). Yoon teaches that the electroluminescent compound can have the following structure,
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are a few examples (paragraph [0055]). These compounds are positional isomers of the applicant’s claimed formula.
Yoon does not specifically teach compounds that meet the applicant’s claimed formula.
The Office points out that sections 2144.09 I and II of the MPEP state " A prima facie case of obviousness may be made when chemical compounds have very close structural similarities and similar utilities. “An obviousness rejection based on similarity in chemical structure and function entails the motivation of one skilled in the art to make a claimed compound, in the expectation that compounds similar in structure will have similar properties.” In re Payne, 606 F.2d 303, 313, 203 USPQ 245, 254 (CCPA 1979). See In re Papesch, 315 F.2d 381, 137 USPQ 43 (CCPA 1963) (discussed in more detail below) and In re Dillon, 919 F.2d 688, 16 USPQ2d 1897 (Fed. Cir. 1991) (discussed below and in MPEP § 2144) for an extensive review of the case law pertaining to obviousness based on close structural similarity of chemical compounds. See also MPEP § 2144.08, paragraph II.A.4.(c).” and “Compounds which are position isomers (compounds having the same radicals in physically different positions on the same nucleus) or homologs (compounds differing regularly by the successive addition of the same chemical group, e.g., by -CH2- groups) are generally of sufficiently close structural similarity that there is a presumed expectation that such compounds possess similar properties. In re Wilder, 563 F.2d 457, 195 USPQ 426 (CCPA 1977). See also In re May, 574 F.2d 1082, 197 USPQ 601 (CCPA 1978) (stereoisomers prima facie obvious).
Isomers having the same empirical formula but different structures are not necessarily considered equivalent by chemists skilled in the art and therefore are not necessarily suggestive of each other. Ex parte Mowry, 91 USPQ 219 (Bd. App. 1950) (claimed cyclohexylstyrene not prima facie obvious over prior art isohexylstyrene). Similarly, homologs which are far removed from adjacent homologs may not be expected to have similar properties. In re Mills, 281 F.2d 218, 126 USPQ 513 (CCPA 1960) (prior art disclosure of C8 to C12 alkyl sulfates was not sufficient to render prima facie obvious claimed C1 alkyl sulfate).
Homology and isomerism involve close structural similarity which must be considered with all other relevant facts in determining the issue of obviousness. In re Mills, 281 F.2d 218, 126 USPQ 513 (CCPA 1960); In re Wiechert, 370 F.2d 927, 152 USPQ 247 (CCPA 1967). Homology should not be automatically equated with prima facie obviousness because the claimed invention and the prior art must each be viewed “as a whole.” In re Langer, 465 F.2d 896, 175 USPQ 169 (CCPA 1972) (Claims to a polymerization process using a sterically hindered amine were held unobvious over a similar prior art process because the prior art disclosed a large number of unhindered amines and only one sterically hindered amine (which differed from a claimed amine by 3 carbon atoms), and therefore the reference as a whole did not apprise the ordinary artisan of the significance of hindered amines as a class.).”
It would have been a prima facie case of obviousness to one of ordinary skill in the art before the effective filing date of the claimed invention to change the attachment point of the aromatic hydrocarbon linking group on the selenium containing heterocyclic groups in the compound of Yoon. These would lead to positional isomers and would be obvious to one of ordinary skill in the art and one of ordinary skill in the art would expect the compounds to act in a similar manner as the compounds taught by Yoon.
Allowable Subject Matter
Claims 3 and 5-11 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: The prior art fails to teach or make obvious the applicant’s claimed compounds or using the applicant’s claimed formula 1 as a host material in electroluminescent device with additional host materials. The closest prior art Yoon et al. (US 2019/0207123) (hereafter “Yoon”) teaches that the electroluminescent compound can have the following structure,
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are a few examples (paragraph [0055]). Yoon teaches that the compounds can be used in electroluminescent, but does not teach or make obvious using the compounds as host materials in electroluminescent devices. Given the lack of teachings in the prior art claims 3 and 5-11 comprise allowable subject matter.
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 ANDREW K BOHATY whose telephone number is (571)270-1148. The examiner can normally be reached Monday-Friday 7am-4pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Curtis Mayes can be reached at (571)272-1234. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ANDREW K BOHATY/Primary Examiner, Art Unit 1759