Thursday, December 27, 2007

More on the Sinorgchem case

Claim 30 of US Patent 5,117,063, at issue in the Sinorgchem case, contains the text:

A method of producing 4-aminodiphenylamine (4-ADPA) comprising the steps of:

a) bringing aniline and nitrobenzene into reactive contact in a suitable solvent system;

b) reacting the aniline and nitrobenzene in a confined zone at a suitable temperature, and in the presence of a suitable base and controlled amount of protic material to produce one or more 4-ADPA intermediates; and

c) reducing the 4-ADPA intermediates under conditions which produce 4-ADPA.

The first sentence of the "summary of the invention" states:

The present invention is directed to a method of preparing 4-ADPA intermediates, namely 4-nitrodiphenylamine (4-NDPA) and the salts thereof, and/or 4-nitrosodiphenylamine (p-NDPA) and/or the salts thereof, wherein aniline and nitrobenzene are brought into reactive contact in a suitable solvent system, and then reacted in the presence of a base and under conditions wherein the amount of protic material, such as water, is controlled.

The DISPUTE arises over text in the "detailed description":

A "controlled amount" of protic material is an amount up to that which inhibits the reaction of aniline with nitrobenzene, e.g., up to about 4% H.sub.2 O based on the volume of the reaction mixture when aniline is utilized as the solvent. The upper limit for the amount of protic material present in the reaction varies with the solvent. For example, when DMSO is utilized as the solvent and tetramethylammonium hydroxide is utilized as the base, the upper limit on the amount of protic material present in the reaction is about 8% H.sub.2 O based on the volume of the reaction mixture. When aniline is utilized as a solvent with the same base, the upper limit is 4% H.sub.2 O based on the volume of the reaction mixture. In addition, the amount of protic material tolerated will vary with type of base, amount of base, and base cation, used in the various solvent systems. However, it is within the skill of one in the art, utilizing the teachings of the present invention, to determine the specific upper limit of the amount of protic material for a specific solvent, type and amount of base, base cation and the like. The minimum amount of protic material necessary to maintain selectivity of the desired products will also depend on the solvent, type and amount of base, base cation and the like, that is utilized and can also be determined by one skilled in the art.

IPBiz notes that the number 4% is preceded by the notation e.g.


Footnote 4 of the case, describing a purported "complex" calculation, is a gem of obfuscation by the majority. All in all, Judge Newman has the better of the legal arguments, and illustrates the inappropriate caselaw relied upon by the majority. The credibility of the majority, in dismissing Example 10 and its significance, might be questioned. In any event, this case is an important one to remember, and to learn from. Good lawyers have to work to insulate their clients even from bad legal analyses.

In terms of a message for patent prosecutors, one should never set off language limiting a claim element in the format:

A "controlled amount" of protic material is an amount up to that which inhibits the reaction of aniline with nitrobenzene, e.g., up to about 4% H.sub.2 O based on the volume of the reaction mixture when aniline is utilized as the solvent

in which the claim element is in quotes, one has the verb "is", and one has e.g., followed by a number. The SAME information could have been conveyed in a NON-LIMITING way.

IPBiz is puzzled by the lack of discussion of the accused infringing method. In the background section of the decision, the majority says of the accused process "aniline is a solvent," NOT aniline is THE solvent. The language relied upon by the majority REQUIRES that aniline be THE solvent. Further, in the same section, one has the rather clumsy sentence:

The amount of water used ... is at least 10 to 15% water throughout the reaction.

Who wrote this?

***
A commenter to an earlier IPBiz post wrote:

Whether that is a good or bad thing, the implication for ppl who write patent claims is pretty clear: don't put in a numerical limitation in your claims (either directly or through lexicographic language in the spec), unless there a specific, known prior art that requires it to be there. Again, for better or worse, there is a lot of hostility toward patents out there these days. The old saving doctrines won't save you anymore.

IPBiz respectfully disagrees. If the drafter of the Flexsys application had utilized numerical limits in the specification as limits were presented, for example, in the Hilton Davis case, there would not have been this problem. Having numerical ranges is a good thing, both to avoid (later-uncovered) prior art and to avoid indefiniteness problems (as were raised in the Sinorgchem case). In the Hilton Davis case, the patentee amended to INCLUDE numerical ranges, which allowed issuance, and, in the end (lest we forget) allowed the patentee to WIN the case under the doctrine of equivalents.

Disclosure of known ranges is a GOOD thing. The problem with the Flexsys patents was the WAY in which the numbers were disclosed, NOT that they were disclosed.

1 Comments:

Blogger David B. Woycechowsky said...

IPBiz respectfully disagrees. If the drafter of the Flexsys application had utilized numerical limits in the specification as limits were presented, for example, in the Hilton Davis case, there would not have been this problem. Having numerical ranges is a good thing, both to avoid (later-uncovered) prior art and to avoid indefiniteness problems (as were raised in the Sinorgchem case). In the Hilton Davis case, the patentee amended to INCLUDE numerical ranges, which allowed issuance, and, in the end (lest we forget) allowed the patentee to WIN the case under the doctrine of equivalents.

This is what dependent claims are for. If the number is in your independent claim, then you really should have a specific, known prior art in mind that requires the number.

In the Warner-Jenkinson case, the upper limit (9.0) of the claimed range was needed to avoid prior art. The lower limit (6.0) of the range was not needed to avoid prior art and should not have been in the independent claim. All it did was to invite an (intentional or unintentional) design-around and a lot of associated litigation for the patentee.

Also, the patentee didn't win in the end. On remand from SCOTUS, Fed. Cir. described the patentee's position thusly:

we remand this case to the district court to conduct an inquiry to ascertain whether [patentee] can rebut the presumption by showing the reason for the amendment of the claim to place a lower pH limit of approximately 6.0 on the ultrafiltration process and whether that reason is sufficient to overcome the estoppel bar to the application of the doctrine of equivalents.

Not a great result for the patentee. From what I see on teh Nets, the case settled before further judicial decisions were rendered. Hilton Davis unquestionably would have been better off if they had presented that lower pH limitation in a dependent claim. And they really should have realized that at the time the Amendment was drafted. As a matter of fact they should have had two dependent claims:

D1. The independent claim with a pH sufficiently high to make the process work good.

and

D2. D1 wherein the pH is at least 6.0.

Some claiming requires more strategic thinking than just setting down the chemical formula.

7:04 AM  

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