Yesterday I wrote:
The Markush group, consisting of A, B, C, mixtures thereof, is exactly equivalent to the phrase: comprising A, B or C.
That's based on
Landis on Mechanics of Patent Claim Drafting by Faber. In sec. 6.2 Faber writes:
Rather than using "selected from the group consisting of", one can simply list the
group members, with "or" preceding the final member.- and -
When materials recited in a claim are so related as to constitute a proper Markush
group, they may be recited in the conventional [Markush] manner, or alternatively. For
example, if "wherein R is a material selected from the group consisting of A, B, C, and D"
is a proper limitation, then "wherein R is A, B, C or D" shall also be considered proper.- and -
Under this modification [...] one could recite a "stripe of copper, silver or aluminum ...."
This is much simpler and covers the same thing as the regular (Markush) group.If you agree with Faber (and me) then:
Claim 1. A paint composition comprising I, II, III, and a pigment selected from
the group consisting of A, B, C, and mixtures thereof.is equivalent to
Claim 2. A paint composition comprising I, II, III, and a pigment, wherein the
pigment is A, B, or C.And presumably you would agree that adding pigment D to a paint composition that infringes claim 2 does not avoid infringement. Then claim 1 could not be engineered around by adding pigment D.
Rich, I followed everything down to the last bit, which to me still seems to go astray. Take your "Paint composition comprising some elements and a pigment, and wherein the pigment
is A, B, or C (or mixtures of)".
A paint wherein the pigment
is {A + non-recited D} does not meet the requirement of "pigment
is A, B, C, or mixtures thereof".
So a paint wherein the pigment
is {A + non-recited D} does not anticipate the claim, and does not infringe it.
