Sections 2, 28(3)
The method of filtering multiple reflections from seismograms
were held to be in a useful art and to be more than mere
calculations. Rejection withdrawn.
This decision deals with Applicant's request for review by the Commissioner
of Patents of the Final Action of application 385,965 (Class 349-16) filed
September 15, 1981. Assigned to Mobil Oil Corporation, it is entitled F-K
FILTERING OF MULTIPLE REFLECTIONS FROM A SEISMIC SECTION. The inventor is
W.H. Ruehle. The Examiner in charge issued a Final Action on November 25,
1983, refusing to allow the application. By letter dated March 25, 1988,
the Applicant withdrew his request for a hearing.
The invention relates to a system, shown in figure 1 below, for obtaining a
seismic section from sets of common depth point (CDP) seismic reflections
which are plotted as per distance (X) and time (T) in arrays (X-T), and
more particularly for enhancing the primary reflections and suppressing the
distortion caused by multiple reflections in the X-T arrays.
(See formula I)
A correction is made at 18 to align the multiple reflections in the CDP
sets 11, followed by stacking the corrected set 22 to obtain an estimate of
multiple reflections. The reverse of the correction 18 is performed to
obtain a time variant time shift 26 of the multiple reflections of the CDP
set, after which that set is transformed 30, 30A, into real and imaginary
portions and then into a frequency and Wave number array (f-k). This array
is inverted 31, to be inversely proportional to the amplitude of the
multiple reflections. The seismic section itself is divided into real and
imaginary parts by the (f-k) transforms 34, 35 whereby the seismic section
is converted into an array S(f-k) of real and imaginary parts by the real
(f-k) transform 34, and the imaginary (f-k) transform 35. The real parts
from 30 and 34 proceed to filter 32, the imaginary parts from 30A and 35
proceed too filter 33. In filters 32, 33, each sample of the S(f-k) arrays
is weighted by a factor inversely proportional to the amplitude of the
corresponding sample in the (f-k) transform of the multiple reflections in
order to suppress multiple reflections. Conversion of the filtered (f-k)
array to a normal X-T array then occurs at 36 and results in a suppression
of the multiple reflections.
In the Final Action, the Examiner said, in part, as follows:
...
In the Schlumberger case the process involved the
transformation of seismic signals representative of well
logging data into more useful data indicative of earth
formation characteristics. The discovery of relating
seismic data by mathematical transformation to the physical
result of formation characteristics was not held
patentable.
The issue in the present case is similar to the
Schlumberger case whereby a series of mathematical
transformations on a seismogram produces a more useful
seismogram. Such discoveries are clearly not patentable in
accordance with Schlumberger. The Re Johnson et al case
referred to by Applicant is not Canadian Law.
Office guidelines 2 and 3 (P.O.R., August 1, 1978, p. 26)
read as follows:
2. Claims to a new method of programming a computer are
not patentable.
3. Claims to a computer programmed in a novel manner,
expressed in any and all modes, where novelty lies
solely in the program or algorithm, are not directed to
patentable subject matter under Section 2 of the Patent
Act.
The present discovery of effecting a series of steps on a
seismogram in order to convert it into a filtered
seismogram providing a more useful seismic section is one
of calculations or programming as referred to in the above
guidelines. Since no novel structural apparatus has been
disclosed this discovery is not patentable.
...
The Applicant argued the merits of his case on the basis of the guidance
provided by several Court cases, amongst them, Schlumberger v. The
Commissioner of Patents 56 C.P.R. (2d) 204, and In re Johnson, Parrack and
Lundsford (1978) 200 USPQ 199.
In discussing the Schlumberger case, the Applicant refers to certain
passages therefrom as follows:
What is new here is the discovery of the various
calculations to be made and of the mathematical formulae to
be used in making these calculations. If those
calculations were not to be effected by the computers, but
by men, the subject matter of the application would clearly
be mathematical formulae and a series of purely mental
operations; as such, in my view, it would not be
patentable.
and
What the appellant claims as an invention here is merely
the discovery that by making certain calculations according
to certain formulae, useful information could be extracted
from certain measurements. This is not, in my view, an
invention within the meaning of Section 2.
The Applicant assesses the In re Johnson case in the following terms, in
part, as follows:
... The invention, for which applicants had sought a
patent, involved methods for removing undesired seismic
signals or noise components from recorded seismic data.
The removal of noise facilitated interpretation of the
seismic data and thereby assisted in the determination of
subterranean structure.
The Court unequivocally stated that, after the decision in
Flook (Parker v. Flook (1978) 198 USPQ 1983), a conclusion
that patent protection is proscribed for all inventions
"algorithmic in character" is overbroad and erroneous. The
Court began its analysis by determining whether the method
claims recited methods of calculating, as were present in
Flook. The Court found two important factual distinctions
between the claims at issue and the claims in Flook.
Unlike the applicant in Flook, the applicants in the
instant appeals (sic) alleged no novel mathematical
formula. Furthermore, the products produced by the
applicants' (sic) claimed process were new, noiseless
seismic traces recorded on a record medium, and not mere
mathematical values. The significant limitations, recited
in the claims, of operating on a recorded, unenhanced
seismic trace led the Court to find that the claims recited
statutory processes and not methods of calculation, under
the Flook criterion.
The Court then went on to consider whether the claims
merely recited mathematical algorithms in a non-statutory
manner, applying the Freeman (in re Freeman (1978) 197 USPQ
464) test to conduct the Benson (409 U.S. 63, 175 USPQ 673
(1972)) inquiry. The Court found that the claims as a
whole, including all of its steps, did not merely recite a
mathematical formula or a method of calculation. Careful
interpretation of each claim in the light of the supporting
disclosure was held to be necessary to determine whether
the claim merely defined a method of solving a mathematical
problem; if not, then the claim defined a process, which is
statutory subject matter.
...
The Applicant explains that his method relates to conversion of a seismic
trace into a more useful version, noting as follows, in part:
...
... The applicant in this application does not merely
claim as an invention the discovery that by making certain
calculations according to certain formulae, useful
information could be extracted from certain measurements,
as was the case in Schlumberger. Rather, the instant
application discloses the production of a new result, i.e.
a new enhanced seismogram, by the method of the invention.
It is submitted that seismograms are physical apparitions
and that the operations upon them are physical steps. It
is submitted that the possible expression of the physical
apparitions in mathematical terms is irrelevant.
...
The issue before the Board is whether or not the application and the claims
present statutory subject matter in view of Sections 2 and 28(3) of the
Patent Act. Claim 1 reads:
A method of filtering multiple reflections from seismograms
representing the earth's formations comprising:
(a) generating first seismograms representing the amplitude
of seismic primary and multiple reflections as a
function of time and distance along a line of
exploration;
(b) transforming said first seismograms into an f-k array
of first real and first imaginary parts representing
amplitude as a function of frequency and wave number;
(c) normal moveout correcting said first seismograms with
the apparent velocity of said multiple reflections to
align said multiple reflections;
(d) stacking said normal moveout corrected first
seismograms having aligned multiple reflections,
(e) inverse normal moveout correcting said stacked first
seismograms to produce second seismograms representing
multiple reflections,
(f) transforming said second seismograms with aligned
multiple reflections into an f-k array of second real
and second imaginary parts,
(g) determining the inverse of said second real and second
imaginary parts of the f-k array of said second
seismograms,
(h) filtering said first real part of the f-k array of said
first seismograms by weighting all samples of said
first real part with corresponding samples of the
inverse of said second real part of the f-k array of
said second seismograms,
(i) filtering said first imaginary part of the f-k array of
said first seismograms by weighting all samples of said
first imaginary part with corresponding samples of the
inverse of said second imaginary part of the f-k array
of said second seismograms, and
(j) transforming said filtered first real and first
imaginary parts into third seismograms representing an
enhanced representation of the earth's formation with
suppressed multiple reflections as a function of time
and distance along said line of exploration.
Both the Examiner and the Applicant have isolated the nature of the
invention, namely, the conversion of a seismogram. The Examiner holds the
conversion amounts to no more than calculations. The Applicant has pointed
out that his invention pertains to work that is done on seismograms whereby
an undesired characteristic previously caused by multiple reflections is
suppressed. The Applicant has explained how the various steps of his
method have produced an enhanced seismogram by removing undesired signals.
He has discussed that whereas in Schlumberger the discovery related to
making certain calculations for extracting certain measurements, the
Applicant's system of conversion of seismic traces to remove undesirable
characteristics presents more than mere calculations, in that the
Applicant's system improves upon the physical steps in producing a more
useful seismogram.
The Examiner has refused the application and the claims in view of Section
28(3) of the Act which reads:
No patent shall issue for an invention that has an illicit
object in view, or for any mere scientific principle or
abstract theorem.
We see that mathematical calculations may be part of the Applicant's system
in that the seismic reflections are stored as an array of samples in a
digital computer, and that Fourier transforms convert the array into
amplitude and a function of frequency and wave number. We observe however,
that the steps of the method work on the seismograms whereby the multiple
reflections are suppressed. It is our opinion these steps bring another
dimension to the kind of invention that the Applicant has presented. We
regard the invention as pertaining to a useful system of filtering multiple
reflections from seismograms, and as such we believe that more than
calculations are involved. We are satisfied the nature of the Applicant's
invention removes it from any of the categories identified in Section
28(3), and hence from being solely algorithmic.
Having so stated that the Applicant's system is useful and does not relate
solely to calculations or algorithms, it is our further view that the
method as described and claimed by the Applicant lies in the field of a
useful art and is permissible under Section 2 of the Patent Act, which
defines invention as follows:
"invention" means any new and useful art, process, machine,
manufacture or composition of matter, or any new and useful
improvement in any art, process, machine, manufacture or
composition of matter.
We recommend therefore, that the rejection of the application and claims
for lack of statutory subject matter under Section 28(3) and Section 2 of
the Patent Act, be withdrawn.
M.G. Brown S.D. Kot
Acting Chairman Member
Patent Appeal Board
I have reviewed the prosecution of this application. I concur with the
findings and the recommendations of the Patent Appeal Board. Accordingly,
I withdraw the refusal of the application air3 the claims, and I remand the
application to the Examiner for prosecution consistent with the
recommendation.
J.H.A. Gari‚py
Commissioner of Patents
Dated at Hull, Quebec
this 19 th day of September 1988
Gowling & Henderson
Box 466, Terminal A
Ottawa, Ontario
K1N 8S3