There is a practice in drafting patent claims called the "Markush" group,
where you can cite a list of multiple items, anyone of which can be used in
part of an invention, usually a chemical.  Quoting Landis quoting the MPEP:

	Ex parte Markush, 1925 C.D. 126; 340 O.G. 839, sanctions, in
	chemical cases, claiming a genus expressed as a group consisting
	of certain specific materials.  This type of claim is employed
	when there is no commonly accepted generic expression which is
	commensurate in scope with the field which the applicant desires
	to cover.  Inventions in metallurgy, refractories, ceramics,
	pharmacy, pharmacology and biology are most frequently claimed
	under the Markush formula but purely mechanical features or
	process steps may also be claimed by using the Markush style
	of claiming.

Typically, you see and use a Markush group as follows:  ".... a halogen
selected    from the group consisting of chlorine and bromine   ".  Note there
is no general phrase the more general than 'chlorine and bromine', but less
specific than 'halogen'.  Typically Markush groups are introduced with the
phrase 'selected from the group consisting of'.  Read the books if you want
to use it, though the books tend to be split on whether or not you should use
it.

Anyways, I recently came across a patent in which the first claim uses the
Markush technique to claim 10,235,904 formulations of a peptide.  With 37
other claims, I suspect the total number of formulations claimed number in
tens of billions.  I thought you all would like to see this claim, if for
no other reason than it quite clearly demonstrates the Markush techique. In
fact, the first claim is nothing more than 8 Markush groups.

The patent is titled "Bradykinin Antagonist Peptides", # 4,801,613, awarded to
Nova Technology Limited on January 31, 1989.  Claim 1 is as follows:





1.  A modified bradykinin type peptide having the formula

		A-Arg-B-C-D-W-X-Y-Z-Arg

and pharmaceutically acceptable salts thereof wherein

a. A is selected from the L-, D- or non configured forms of the group
consisting of
    (i) hydrogen
   (ii) Arg
  (iii) Lys-Lys
   (iv) Phe
    (v) Thi
   (vi) Lys
  (vii) Met-Lys
 (viii) Gly-Arg-Mey-Lys;

b. B is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Azetidine-2-Carboxylic acid (Azt)
   (ii) Thiazolidine-2-Carboxylic acid (Thz)
  (iii) Isonipecotic acid (Inip)
   (iv) Pro
    (v) 2,3-Dehydroproline (delta Pro)
   (vi) 4-Hydroxyproline (Hyp)
  (vii) Aib;

c. C is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Azetidine-2-Carboxylic acid (Azt)
   (ii) Thiazolidine-2-Carboxylic acid (Thz)
  (iii) Isonipecotic acid (Inip)
   (iv) Pro
    (v) 2,3-Dehydroproline (delta Pro)
   (vi) 4-Hydroxyproline (Hyp)
  (vii) Aib;

d. D is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Gly
   (ii) Ala
  (iii) Sar;

e. W is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Phe
   (ii) beta-(2-Thienyl)-Alanine (Thi)
  (iii) O-Methyltyrosine (OMT)
   (iv) beta-(2-Pyridyl) Alanine (Pal)
    (v) Para-Chloro-L-Phenylalanine (CLF)
   (vi) Para-Nitrophenylalanine (PNF)
  (vii) beta-(2-Naphthyl)-Alanine (Nal)
 (viii) Leu;

f. X is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Ser
   (ii) Gly
  (iii) Phe
   (iv) Para-Chloro-D-phenylalanine (CDF)
    (v) Nal
   (vi) Pal
  (vii) Thi
 (viii) pCl-Phe;

g. Y is a D- configured form selected from the group consisting of
    (i) DNal
   (ii) DPNF
  (iii) DPhe
   (iv) DTyr
    (v) DPal
   (vi) DOMT
  (vii) DThi
 (viii) DAla
   (ix) DTrp
    (x) DHis
   (xi) D-Homo-Phe (DhPhe)
  (xii) pCl-DPhe (CDF)
 (xiii) DPhg
  (xiv) D-Val
   (xv) DIle
  (xvi) DLeu
 (xvii) MDY; and

h. Z is selected from the L-, D- or non configured forms of the group
consisting of
    (i) Phe
   (ii) beta-(2-Thienyl)-Alanine (Thi)
  (iii) O-Methyltyrosine (OMT)
   (iv) beta-(2-Pyridyl) Alanine (Pal)
    (v) para-Chloro-L-Phenylalanine (CLF)
   (vi) para-Nitrophenylalanine (PNF)
  (vii) beta-(2-Naphthyl)-Alanine (Nal)
 (viii) Leu.

==============================================================================

Multiply out the numbers for each group, 8 * 7 * 7 * 3 * 8 * 18 * 8 and you
get 10,235,904 combinations. A pretty good way to achieve very broad coverage.
The Markush group is a useful technique to learn about if you plan to draft
your own claims.  Anyways it is a very pretty example - I couldn't resist
sharing it.

Greg Aharonian
Internet Patent News Service
(for subscription info, send 'help' to   patents@world.std.com)
(for prior art search services info, send 'prior' to patents@world.std.com)