COMMISSIONER' S DECISION
Breadth of Claims; Support in Disclosure; Rule 44(3) - Microfilters comprising
polymeric binders and fillers
Filters for bacteria were made up of polymeric resinous binders containing inorganic
fillers. The examiner felt the binders should be restricted to polyvinyl chloride
It was concluded that it was not unreasonable to conclude that other known
phermoplastic resins would obviously be useful, and the claims need not be
restricted to the specific polymer described in detail. The principles expressed
in Burton Parsons v Hewlett Packard were considered to be applicable. Rule 44(3)
(now R.45(3)) was not raised when claims previously rejected were reinstated.
**************
Patent application 188024 (Class 400-50), was filed on December 12,
1973 for an invention entitled "Microporous Sub-Micron Filter Media."
The inventor is Bruce S. Goldberg. The Examiner in charge of the
application took a Final Action on January 19, 1978 refusing to allow
it to proceed to patent.
The claims are directed to a filtering medium useful in separating small
particles, such as bacteria, from fluid media in which they are
suspended. The filters comprise inorganic fillers dispersed through
a polymeric resinous binder, containing a network of open pores, and
have certain advantages over prior filters.
The Examiner rejected the claims for being broader than the invention
disclosed. In particular he considered that they should be restricted to
polyvinyl chloride resins, and copolymers thereof, rather than covering
thermoplastic polymers generally, as they now do. We must assess whether
that objection is proper.
The Examiner had rejected all the claims for that reason, but narrowly
viewed the objection is applicable only to claims 1 and 11 (as not.:
proposed). The other claim are dependent upon claims 1 and 11, and as
now drafted would fall if the principal claims fell. However, the subject
matter in them is,per se, unobjectionable, and if dependent upon an
allowable claim, would be acceptable. For example, if claims 2 and 12
were drafted in independent form and the other claims made dependent upon
them, the claims other than 1 and 11 would be allowable. We will con-
sequently limit our attention to claims 1 and 11. If they fall, the
remaining claims must be revised as just indicated. If they stand, the
remaining claims will also stand as they are now drafted.
The Examiner had certain other objections to the form of claim 12, but they
have been met by the proposed amendment of June 19, 1978, which amendment
makes other improvements to the claims. We consequently believe that
amendment should be entered, and will proceed to consider the claims of
June 19, 1978.
We quote the following portion of the Examiner's action to show the nature
of his objection.
...
The expression "polymeric resinous matrix" (claim 1) "polymeric
resinous binder" (claims 11, 21, 22 and 23) is far too broad.
These expressions appear in the disclosure, however, the only
"polymeric resinous binder" (and the "matrix" formed therefrom)
disclosed is in fact polyvinyl chloride or vinyl chloride copolymers
of the type generally considered to fall within the term "polyvinyl
chloride". An inspection of the disclosure reveals that the "polymeric
resinous binder" or "matrix" is in fact "polyvinyl chloride" or
"vinyl chloride copolymers". The term "polyvinyl chloride resinous
binder or matrix" is the only exemplified polymer (see page 4,
lines 14 to 18, page 4a, lines 3 to 5, page 5, lines 2 to 3, page 5, line
13 to page 6, line 1, page 7, lines 5 to 6, and Examples 1, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15). The exemplified polymers are
"GEON 103 E~" (example ~, also utilised in examples 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13) "ESCAMBIA 6240" (example 14) and "AIRCO
401"; all these are vinyl chloride resins. Applicant disclosed
that a thermoplastic resin binder is an essential ingredient (page 4c,
line 8 to page 5, line 12) in the words "the following essential
ingredients: (1) a thermoplastic resin binder, for example, resinous
polyvinyl chloride"; (page 5, lines 1 to 3). Thus it is clear that
applicant only teaches vinyl chloride resin binders as a useful
material. This is not sufficient to support either the term "thermo-
plastic resin binder" which includes materials not contemplated by
applicant, and is totally insufficient to support the term "polymeric
resinous binder" which definitely can include wide classes of
materials not contemplated by applicant.
...
He has further pointed out that after the first report Applicant complied
with the Examiner's objections and limited the claims to polyvinyl chloride
resins (letter of Nov. 5, 1976), but reintroduced the broader aspects in
the claims of December 1, 1977. Whether such action advanced the prosecu-
tion to allowance within the meaning of Rule 44(3) was not questioned at
the time, and prosecution continued as if the application were not
abandoned under Section 32.
The Applicant's position is as follows:
...
...In the present instance, the examples deal with PVC type
resins, but there is no reason to doubt the utility of the
invention for other resins.
By way of example, Applicant would point out that the in-
vention is useful with the following polymers among others:
polyethylene polypropylene
chlorinated polyethylene polyurethane
polystyrene polyvinylidene
Such compounds can be used with relatively minor testing or
development work. Such further work would certainly not amount
to making a new invention, but is considered within the scope
of the invention already made. In other words, such modifica-
tions and adaptations as would be necessary for the use of
polymers other than PVC would be known and/or would be obvious
to persons of ordinary skill in the art. (Underlining added)
...
and
...
The Applicant in the disclosure has given working examples
of a group of vinyl chloride materials which are clearly and
definitely useful and stated in the disclosure that other thermo
plastic resins would work. Applicant then recited a set of
criteria for judging such other materials, namely on page 6 of
the disclosure. It is clear that Applicant has always contemplated the
use of materials other than PVC type materials.
...
The paragraph on page 6 of the disclosure referred to, begins on page 5,
and reads as follows:
...
In practicing the invention, it is preferable to employ a vinyl
chloride resin binder of the "EP" or "easy processing" type.
An EP resin is characterized by resin particles which are porous
and highly absorbent, as compared to commercial resin particles
having a hard glossy beaded appearance. A good example of a
suitable thermoplastic resin binder is a nonplasticized, gamma
vinyl chloride homopolymer resin such as that commercially avail-
able from B.F. Goodrich Company under the trademark Geon 103 EP.
The vinyl chloride resin binder may also be a copolymer of vinyl
chloride and a shall amount (for example up to about 15%) of a
monoethylenic monomer, i.e. vinyl acetate, vinylidene chloride,
propylene, or ethylene. Exemplary copolymers of the latter type
suitable for use with the present invention may be a propylene
modified vinyl chloride resin such as that commercially available
from the Air Products Company under the trademark Airco 401, or
a vinyl acetate modified vinyl chloride resin also commercially
available from Air Products Company under the trademark Escambia
6240. Obviously, other thermoplastic resinous binders could also
be used as will occur to those skilled in the art as long as
the thermoplastic resin is a material which (1) can be converted
to a doughy, semi-plasticized state with the aid of a solvent so
as to be readily capable of shaping by extrusion or calendering
while in this semi-plasticized state, and which then, upon removal
of solvent and consequently deplasticization, retains the resulting
shape at whatever temperature it is ultimately intended to
function; and (2) which is chemically and physically stable under
the conditions of intended use, that is, if it is intended to
function as filter media the resin should resist attack by the
fluids or gases within which it will be used, it should be tough
and have adequate tensile strength, and it should be able to with-
stand the ambient temperatures under which the filter media are
expected to be used and function.
...
The term "thermoplastic polymeric resins" covers many different resins, such
as A.B.C. (acrylonitrile- butadiene-styrene), acetals, acrylics such as methyl
methacylates, cellulosics, chlorinated polyethanes, fluoroplastics
(e. g. polytetrafluorethylenes), nylons, ionomers, nylons (polyamides), certain
polyesters, polycarbonates, polyethylene, polyphenylene sulphides, polypropylenes,
polyimides, polystyrene, polysulphones, phenoxides, polyvinyl chlorides, certain
polyurethanes, and others, none of which were mentioned in the original
disclosure. It is this thus-demonstrated broad scope of the term "thermoplastic
polymer" that gave rise to the Examiner's objection.
In Hoechst v Gilbert 1966, S.C.R. 189 at 194 the Supreme Court of Canada
has adopted the view that no one may obtain a valid patent for an unproved
and untested hypothesis in an unchartered field. In B.V.D. v. Canadian
Celanese 1936 Ex. C.R. 139 at 148 and 1937 S.C.R. 221 at 236 the courts spoke
out about claims to mere adumbrations and "going beyond the invention."
In Boehringer Sohn v Bell Craig 1962 Ex.C.R. 201 at 339 & 241 it was indicated
that an inventor cannot patent more than he has invented. In Soci‚t‚ Rh“ne-
Poulenc v Ciba (1967) 55 F.P.C. 174 at 201-205 and (1968) S.C.R. 950 the
claims were invalid because the majority of the substances of the class had
never been made or tested by anyone. See also in Re May & Baker (1948)
65 R.P.C. 255 (1949), 66 R.P.C. 8, and (1950) 67 R.P.C. 23 and Esair's
application (1932) 49 R.P.C. 85. It is thus clear that there are limits to
the breadth of claims that may be made in any particular case, and it is
doubtless with that thought in mind that the Examiner rejected the present
claims.
An Applicant should be able, however, to put forward a claim in generic
terms to a group of like substances, all of which need not have been prepared
or tested, where one skilled in the art would consider it reasonable and
possible to make a sound prediction that the group as a whole would be
effective. In some instances that area may be quite broad, in others
extremely narrow, depending in large part upon the state of the prior art,
in part upon the extent to which the Applicant himself has explored that
area. Further, where such exploration is needed, he should have explored
the area before he filed his application for patent. Otherwise the invention
was speculative when filed, and only completed subsequently.
This is the principle which we followed in the recent case of Monsanto v
Commissioner of Patents, one reviewed both by the Federal Court of Canada.
34 C.P.R. (2d) 1, and by the Supreme Court on June 28, 1979. Both those
courts expressed approval of the principle, though the majority of
the Supreme Court differed in finding that the principle was satisfied in
the factual situation then before it.
In the present case the Applicant is not claiming new chemical compounds whose
properties are unknown. Rather he is claiming a mixture of known resins with
other known materials, and the invention is related to the physical properties of
the resultant composition. Thermoplastic polymeric resins as a group
are well known, and we think it would be reasonable for one skilled in the
art to predict that many of them would have the desired binding properties to
hold together the other ingredients of the mix.
In many respects we are facing a situation similar to that which came up in
Burton Parsons v Hewlett-Packard F.C.C., 7 C.P.R. (2d) 198 (1973); F.C.C.
Appeal Div. 10 C.P.R. (2d) 126 (1973) S.C.C. 17 C.P.R. (2d) 97 (1975).
That case dealt with a conductive cream to be used in making electro-
cardiograms, and comprising an aqueous emulsion of "highly ionizable salts."
In that case the Supreme Court said (p. 105):
In the present case, the invention relates to a mixture and
a process for making it. This mixture is of no fixed composi-
tion. A great many different substances can be used, hundreds
if not thousands, said Shansky. The essential is to combine a
highly ionizable salt with an aqueous emulsion. As a result of
this combination, the wetting action of the emulsion on the
skin makes it possible to use the salt in a low concentration
(from 1 to 10%). If the patent is to have a practical value,
it must cover all the emulsions and salts which can yield the
desirable result, namely, all "emulsions with the outer phase
or the continuous phase being water" and all salts that are
highly ionizable enough to carry an electric current with low
resistivity on the skin excluding only such substances as are
not compatible with normal human skin. The evidence makes
it clear that this was obvious to any person skilled in the art
because the characteristics of suitable emulsions and of suitable
salts were well known. Only the combination was new.
This is the distinguishing feature from the other cases in
which the properties of xanthates in froth flotation and
those of some substituted diamines as antihistamines were
the object of the invention. The inutility of cellulose
xanthate in Minerals Separation, as well as that of some
isomers of triplelennamine in Rh“ne-Poulenc was not known
to the prior art. This is totally unlike the undesirable properties
of some highly ionizable salts which Hewlett-Packard listed
as objectionable. Their no~ious character was well known and
no man skilled in the art would have thought of using them
in making a cream for use with skin contact electrodes any
more than any such worker would have needed to be told that in
making such a cream, he had to use such proportions of liquid
and of emulsified material as to obtain a suitable consistency.
and It is stressed in many cases that an inventor is free to make
his claims as narrow as he sees fit in order to protect himself
from the invalidity which will ensue if he makes them too broad.
From a practical point of view, this freedom is really quite limit-
ed because if, in order to guard against possible invalidity, some
area is left open between what is the invention as disclosed and
what is covered by the claims, the patent may be just as worthless
as if it was invalid. Everybody will be free to use the invention
in the unfenced area. It does not seem to me that inventors are to
b a looked upon as Shylock claiming his pound of flesh. In the present
case, there was admittedly a meritorious invention and Hewlett-
Packard, after futile attempts to belittle its usefulness, brazenly
appropriated it. It was in no way misled as to the true nature of
the disclosure nor as to the proper methods of making a competing
cream. The objections raised against the claims really are that,
except those pertaining to some specific embodiments of the invention,
the others are so framed as to cover every practical embodiment,
leaving to the man skilled in the art, the task of avoiding unsuitable
materials in the making of the mixture, a task which any man
skilled in the art ought to be able to perform without having
to be told because any unsuitability depends on well-known properties.
No unexpected or generally unknown unsuitability was proved or
even suggested, which makes this case quite unlike Minerals
Separation or Rh“ne-Poulenc.
In the present case we are also dealing with a mixture of known substances
with known properties. The invention involves the use of their known physical
property, rather than newly discovered chemical properties. We think it
could be evident to those skilled in the art that once it was found that
polyvinyl chloride resins could be used as binders that most if not all thermo-
plastic resins would be equally suitable. For that reason we recommend that
the rejection of claims 1 and 11 be withdrawn.
G.A. Asher
Chairman
Patent Appeal Board, Canada
Having considered the prosecution of this application and the recommend-
ation of the Patent Appeal Board, with which I concur, I direct that the
resection made be withdrawn. The application is to be returned to the
Examiner to resume prosecution of claims 1 - 20 as submitted on June 19, 1978.
J.H.A. Gariepy
Commissioner of Patents
Dated at Hull, Quebec
this 19th. day of November, 1979
Agent for Applicant
Gowling & Henderson
Box 466, Terminal A
Ottawa, Ont.