Compound "Anticipated" by Incorrect Structural Formula
Examiner Rejects Compound Claim as Anticipated by Error in Prior Art
I recently worked on a case where the examiner rejected a claimed compound as anticipated by an incorrect structural formula. The case made for an interesting case of “anticipation” under 35 USC 102.
Conventionally, an examiner rejects a compound as anticipated upon finding that compound in a structural database. But, this time, the structure was clearly wrong. The author assigned the wrong structure to a molecule that he made. Based on common sense, rejecting the compound for lack of novelty seemed improper because the rejection was based solely on an error cataloging a compound by the wrong structure. The claimed compound was—in fact—new.
During prosecution, all parties knew the right result. The examiner wanted to allow the claim. But the examiner could not get around finding an exact structural match. The applicant, knowing he was the first to make the compound, was understandably frustrated by the Examiner’s insistence that his invention was “not new.”
Error in Prior Art’s Structural Formula
Here are a few relevant facts:
- The claim at issue was to a chemical compound, defined by a generic structural formula (“the inventor’s claimed genus”).
- The prior art disclosed a specific structural formula falling within the inventor’s claimed genus.
- The prior art structural formula was wrong. The author of that art made a mistake when assigning a structural formula to a compound that he made.
Structural Match Found by Examiner
When searching for the claimed compound by structural formula, the examiner finds a structure that clearly falls within the claimed genus. The examiner issues a rejection for anticipation under 35 USC 102 (a). A disclosure of a chemical species anticipates a genus comprising it. “A generic claim cannot be allowed to an applicant if the prior art discloses a species falling within the claimed genus.” The species in that case will anticipate the genus. In re Slayter, 276 F.2d 408, 411, 125 USPQ 345, 347 (CCPA 1960); In re Gosteli, 872 F.2d 1008, 10 USPQ2d 1614 (Fed. Cir. 1989).
Section 102 (a) provides that “A person shall be entitled to a patent unless the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.” From the examiner’s perspective, the scientific literature showed a clearly anticipatory compound.
The claimed compound is new, despite the structural match.
Upon receiving the Office Action, the inventor looks at the prior art and immediately sees the mistake. The inventor is the world’s expert in the class of molecules at issue. He provides an affidavit explaining the mistake. He explains that it would be impossible for the prior art’s disclosure to provide his claimed compounds.
When arguing fails to remove the rejection, the inventor experimentally confirms the mistake by reproducing the prior art’s procedure for making the compound. This evidence also does not remove the rejection. The examiner reasons that an ordinary artisan would have recognized how to make the claimed compounds based on (a) the prior art’s disclosure and (b) ordinary skill. (Notably, this conversation is directed to whether the prior art was enabling).
Arguing Novelty over a Structural Error
Below, I describe how an applicant can work with the case law to remove the rejection. The theory relies on two firmly established principles in patent law. First, a “compound” is not limited to its structural formula but includes all aspects of the compound. Second, anticipation requires prior art disclosing exactly the same invention found in the claim at issue.
First, remember that the term compound is a legally significant term. It means the compound and all of it’s properties. “From the standpoint of patent law, a compound and all of its properties are inseparable; they are one and the same thing.” In re Papesch, 315 F.2d 381, 391 (CCPA 1963).
Also, anticipation means that the prior art compound is exactly the same as the claimed compound. “[A]nticipation under § 102 can be found only when the reference discloses exactly what is claimed and that where there are differences between the reference disclosure and the claim, the rejection must be based on § 103 which takes differences into account.” Titanium Metals Corp. v. Banner, 778 F.2d 775, 227 USPQ 773 (Fed. Cir. 1985).
Comparing Structural Formulas
Comparing any two compounds could lead to four results because a compound includes (1) structure and (2) properties:
- Two compounds that are exactly the same (same structure and properties)
- Two compounds differing in structure only
- Two compounds differing in structure and properties
- Two compounds differing in properties only
Anticipation requires option number #1. Each of the other three scenarios include some differences, which should move the analysis into the framework of obviousness under 35 USC 103.
A case where the prior art only discloses the structural formula (by mistake) fails to provide a compound having the same properties as the claimed compound. Accordingly, that case falls into scenario #4, above. Because the properties are different, the compounds are different. Any difference means no anticipation. All differences must be considered under 103.
I would welcome other thoughts on this sort of rejection. Please feel free to add your thoughts by using the comments section below.