IN THE UNITED STATES PATENT & TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD. WESTERNGECO L.L.C., Petitioner,

IN THE UNITED STATES PATENT & TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD WESTERNGECO L.L.C., Petitioner, v. PGS GEOPHYSICAL AS, Patent Owner. Case IPR2015-00311 Patent U.S. 6,906,981 PETITION FOR INTER PARTES REVIEW OF CLAIMS 31-38 OF U.S. PATENT NO. 6,906,981 UNDER 35 U.S.C. 312 AND 37 C.F.R. 42.104

TABLE OF CONTENTS I. OVERVIEW OF THE PETITION... 1 II. MANDATORY NOTICES - 37 C.F.R. 42.8(a)(1)... 8 III. PAYMENT OF FEES - 37 C.F.R. 42.103... 9 IV. REQUIREMENTS FOR INTER PARTES REVIEW... 9 A. Grounds for Standing- 37 C.F.R. 42.104(a)... 9 B. Identification of Claims for Which Review Is Requested and Relief Requested 37 C.F.R. 42.104(b)(1) and 42.22(a)(1)... 10 1. Prior Art Patents and Printed Publications... 10 2. Statutory Grounds of Challenge 37 C.F.R. 42.104(b)(2)... 11 V. THE 981 PATENT... 11 A. Overview of the 981 Patent... 11 B. Prosecution History of the 981 Patent... 13 VI. CLAIM CONSTRUCTION... 13 A. wavelet time... 14 VII. LEVEL OF ORDINARY SKILL IN THE ART... 15 VIII. IDENTIFICATION OF HOW THE CHALLENGED CLAIMS ARE UNPATENTABLE - 37 C.F.R. 42.104(b)(4)-(5) and 42.22(a)(2)... 15 A. Claims 31, 32, and 36-38 are anticipated by De Kok... 16 B. Claims 31-38 are obvious in view of the combined teachings of Beasley and Timoshin... 24 1. The proposed grounds based on Beasley and Timoshin are not redundant to the grounds based on De Kok.... 24 2. Claim 31... 25 3. Claim 38... 30 4. Claims 32-35.... 31 a. Claim 32.... 31 b. Claim 33.... 32 c. Claims 34.... 32 i

d. Claim 35.... 32 5. Claims 36 and 37.... 33 C. Claims 31-38 are obvious in view of the combined teachings of Beasley and Edington... 35 1. The proposed grounds based on Beasley and Edington are not redundant to the grounds based on De Kok or the ground based on Beasley and Timoshin... 35 2. Claim 31... 37 3. Claim 38... 41 4. Claims 32-35.... 42 a. Claim 32.... 43 b. Claim 33.... 43 c. Claims 34.... 43 d. Claim 35.... 44 5. Claims 36 and 37.... 44 IX. CONCLUSION... 45 ii

I. OVERVIEW OF THE PETITION WesternGeco L.L.C. ( Western or Petitioner ) respectfully requests inter partes review ( IPR ) for claims 31-38 of U.S. Patent No. 6,906,981 ( the 981 patent, Ex. 1001) in accordance with 35 U.S.C. 311-319 and 37 C.F.R. 42.100 et seq. The prior art cited in this Petition demonstrates that the seismic surveying method recited in claims 31-38 of the 981 patent was widely known and used well before the 981 patent s purported priority date and, accordingly, claims 31-38 of the 981 patent should not have issued. The 981 patent is directed to seismic surveying, a well-known method of mapping geological formations with sound wave reflections. A basic overview of the principles and elements of seismic surveying are provided in an article titled How Modern Techniques Improve Seismic Interpretation that appeared in the April, 1994 issue of World Oil magazine. ( World Oil Article, Ex. 1008.) The Federal Circuit has emphasized the importance of considering such background information as part of the obviousness determination, stating: In recognizing the role of common knowledge and common sense, we have emphasized the importance of a factual foundation to support a party s claim about what one of ordinary skill in the relevant art would have known. See, e.g., Mintz v. Dietz & Watson, Inc., 679 F.3d 1372, 1377 (Fed. Cir. 2012); Perfect Web Techs., Inc. v. InfoUSA, Inc., 587 F.3d 1324, 1328 (Fed. Cir. 2009). One form of evidence to provide such a 1

foundation, perhaps the most reliable because not litigation-generated, is documentary evidence consisting of prior art in the area. Randall Mfg. v. Rea, 108 USPQ2d 1727, 1732-1733 (Fed. Cir. 2013). As explained in the World Oil Article, reflection seismology was first applied in the 1920s. (Ex. 1008, at 85.) Reflection seismology uses induced acoustic reflections of rock layers. (Id.) Vibrations are generated in the earth with acoustic sources, and reflections are recorded with receivers. (Id.) Most marine acquisition sound sources are air guns that repeatedly displace water volumes, and marine receivers are pressure sensitive devices called hydrophones. (Ex. 1008, at 86.) On land, sources include explosives or truck mounted vibrators, and receivers are geophones that detect slight ground movements. (Id.) Regardless of whether it is a land-based geophone or a marine-based hydrophone, the basic principle of operation is the same each receiver converts pressure or ground disturbances to electrical impulses, and the digitally recorded electrical pulses of an array or group of receivers are transmitted for each station and transmitted, via cable or telemetry, to recording computers. (Id.) 2

Figure 1 of the World Oil Article, reproduced below, is a simplified diagram of the seismic principle used in both land and marine surveys. In the example shown in Figure 1 of the World Oil Article, the Horizon 1 reflection results from an impedance contrast between Layers 1 and 2; likewise for Reflection 2 emanating from Horizon 2. (Ex. 1008, at 86.) Ray paths are described by Snell s Law and bend at each layer interface (horizon). (Id.) Subsurface horizons are imaged repeatedly by source-receiver pairs as shooting progresses to each consecutive line location. (Id.) Given the similarities in their principles of operation, it is not surprising that both land-based and marine-based seismic surveys were known to share some common methodologies to improve signal to noise ratios. The World Oil Article 3

explains one such well-known methodology that was shared by both land-based and marine-based seismic surveys: the common midpoint (CMP) gather. A CMP gather is a collection of all combinations of source-receiver pairs which records energy from the same midpoint location, therefore containing travel paths from near to far offset traces. (Ex. 1008, at 86.) The World Oil Article explains that [t]his redundancy increases the signal to noise ratio when traces are processed and summed. (Id.) In towed marine surveying, a vessel tows one or more of the seismic energy sources, and the same, or a different vessel tows one or more streamers, which are series of seismic sensors affixed to a cable. Returning now to the 981 patent, Figure 1 of the 981 patent, reproduced below, shows two or more sources (SA1, SA2), such as air guns, that are fired to generate seismic energy that travels through the earth. A group of sensors (2a-2d), such as hydrophones, record the returning echoes as a function of time. (Ex. 1001, 1:22-2:37.) 4

As noted in the World Oil Article, [i]t was common to use synchronized source arrays to increase, or focus, energy at each shot. (Ex. 1008, at 86.) For example, as explained in the background portion of U.S. Patent No. 6,545,944 to de Kok ( De Kok, Ex. 1003), which was filed more than a year prior to the earliest filing date claimed by the 981 patent, the use of multiple sources firing simultaneously into the same recording system was known to be an attractive option to increase the field survey efforts at relatively low incremental cost. (Ex. 1003, 2:27-30.) De Kok explains that simultaneous firing is particularly economical when additional sources can easily and cheaply be deployed, such as airgun arrays in a marine situation. (Ex. 1003, 2:30-33.) As explained in the declaration of Luc T. Ikelle, Ph.D. ( the Ikelle declaration, Ex. 1002), the simultaneous activation of multiple sources can raise complications relating to noise generation and distinguishing sources from each other. (Ex. 1002, 32-33.) It was long-known in the land seismic context that if two sources were asynchronous, the interfering signal could be treated as noise and distinguished through simple CMP binning. Soviet Union Patent No. 1,543,357 to Timoshin et al. ( Timoshin, Ex. 1005), published more than a decade prior to the earliest filing date claimed by the 981 patent, discloses using random numbers as firing delays for sources to distinguish between separate sources during CMP processing. U.S. Pat. No. 4,953,657 to Edington ( Edington, Ex. 1006), which was also filed more than a decade prior to the earliest filing date claimed by the 981 patent, discloses shooting at 5

least two seismic energy sources substantially simultaneously with a determinable time delay between the activation of each source, and then shooting the sources at least a second time substantially simultaneously with a different determinable time delay between the activation of each source from the determinable time delay used in at least one previous shooting. (Ex. 1006, 2:1-13.) Edington explains that the determinable time delays is preselected, and is selected so that the difference in time delay between any two shootings enables the signal received from the first activated source to be distinguished from the signal received from the second activated source. (Ex. 1006, 2:15-20.) Further, U.S. Patent No. 5,924,049 to Beasley et al. ( Beasley, Ex. 1004) discloses a broad toolbox of techniques for separating simultaneous sources. As explained in the Ikelle declaration, it was well known in the seismic surveying art prior to the earliest filing date claimed by the 981 patent to encode signals for later separation by modifying the source signatures. This included varying the amplitude, frequency, and/or firing time of the source signature. (Ex. 1002, 34-35.) More sophisticated techniques, such as those disclosed in De Kok, went beyond distinguishing the two sources and disclosed timing techniques that would reinforce the two signals to improve their informational content. Specifically, unlike the 981 patent, De Kok discloses time delay encoding techniques which rely on programmed time delays in the field and polarity decoding in the processing center. 6

Nevertheless, the 981 patent purports to have invented the concept of time varying seismic source signals. Claim 1 of the 981 patent recites: 31. A method for determining signal components attributable to a first seismic energy source and to a second seismic energy source in signals recorded from seismic sensors, the first and second sources and the sensors towed along a survey line, the first source and the second source fired in a plurality of sequences, a time delay between firing the first source and the second source in each firing sequence being different than the time delay in other ones of the firing sequences, the method comprising: determining a first component of the recorded signals that is coherent from shot to shot and from trace to trace; time aligning [the] 1 recorded signals with respect to a firing time of the second source in each firing sequence; and determining a second component of the signals that is coherent from shot to shot and from trace to trace in the time aligned signals. This time-variation was long-used in the prior art to separate simultaneous sources. For example, De Kok discloses more sophisticated time delay encoding techniques than those disclosed in the 981 patent, that nevertheless fully anticipate claim 31 of the 981 patent and several of the claims that depend therefrom. In addition, the combined teachings of Beasley and either of Timoshin or Edington render all of the claims of the 981 patent obvious. Beasley is directed to 1 It is clear from the prosecution history that the Applicant intended claim 31 to recite the instead of die. (See Ex. 1007, claim 31, p. 12.) 7

marine seismic surveys that include firing seismic sources simultaneously or near simultaneously in which the sources may be arranged to emit encoded wavefields using any desired type of coding and discloses time separation of the sources, but does not explicitly disclose the type of asynchronous time separation claimed in the 981 patent. (Ex. 1004, 7:54-56.) It would have been obvious to employ the known time encoding techniques disclosed in either of Timoshin or Edington in the system of Beasley to achieve the predictable result of distinguishing sources that are fired either simultaneously or near simultaneously. II. MANDATORY NOTICES - 37 C.F.R. 42.8(A)(1) Petitioner provides the following mandatory disclosures. A. Real Parties-In-Interest - 37 C.F.R. 42.8(b)(1) WesternGeco, L.L.C., Schlumberger Technology Corporation, Schlumberger Holdings Corporation; Schlumberger B.V., Schlumberger, Limited, and Schlumberger Services, Inc. are the real parties-in-interest. B. Related Matters- 37 C.F.R. 42.8(b)(2) The 981 patent is asserted in co-pending litigation captioned as WesternGeco LLC v. Petroleum Geo-Services, Inc. et al., Southern District of Texas, Case No. 4:13-cv- 02725. C. Lead and Back-Up Counsel- 37 C.F.R. 42.8(b)(3) Petitioner provides the following designation of counsel: 8

Lead Counsel: Scott McKeown (Registration No. 42,866) Backup Counsel: Christopher A. Bullard (Reg. No. 57,644) D. Service Information - 37 C.F.R. 42.8(b)(4) Papers concerning this matter should be served as follows: Email: CPdocketMckeown@oblon.com CPdocketBullard@oblon.com Post: Oblon Spivak, 1940 Duke St., Alexandria, VA 22314 Telephone: 703-412-6297 Facsimile: 703-413-2220 III. PAYMENT OF FEES - 37 C.F.R. 42.103 The undersigned authorizes the Office to charge the fees set forth in 37 C.F.R. 42.15(a) as required by 37 C.F.R. 42.103 for this Petition for Inter Partes Review to Deposit Account No. 15-0030; any additional fees that might be due are also authorized. IV. REQUIREMENTS FOR INTER PARTES REVIEW A. Grounds for Standing- 37 C.F.R. 42.104(a) Pursuant to 37 C.F.R. 42.104(a), Petitioner hereby certifies that the 981 patent is available for inter partes review and that the Petitioner is not barred or estopped from requesting inter partes review challenging the claims of the 981 patent on the grounds identified herein. This is because the 981 patent has not been subject to a completed estoppel based proceeding of the AIA, and the counterclaim served on Western referenced above in Section II(B) was served within the last 12 months. 9

B. Identification of Claims for Which Review Is Requested and Relief Requested 37 C.F.R. 42.104(b)(1) and 42.22(a)(1) Pursuant to 37 C.F.R. 42.104(b) and (b)(1), Petitioner requests inter partes review of claims 31-38 of the 981 patent, and that the Patent Trial and Appeal Board ( PTAB ) determine the same to be unpatentable. 1. Prior Art Patents and Printed Publications Petitioner relies upon the following patents and printed publications: Exhibit 1003 U.S. Patent No. 6,545,944 to de Kok ( De Kok ), filed May 30, 2001 and issued April 8, 2003. De Kok is available as prior art under 35 U.S.C. 102(e). Exhibit 1004 U.S. Patent No. 5,924,049 to Beasley et al. ( Beasley ), filed January 30, 1998 and issued July 13, 1999. Beasley is available as prior art under 35 U.S.C. 102(b). Exhibit 1005 Soviet Union Patent No. 1,543,357 to Timoshin et al. ( Timoshin ), filed January 7, 1988 and published February 15, 1990. Timoshin is available as prior art under 35 U.S.C. 102(b). Exhibit 1006 U.S. Patent No. 4,953,657 to Edington ( Edington ), filed February 14, 1989 and issued September 4, 1990. Edington is available as prior art under 35 U.S.C. 102(b). 10

2. Statutory Grounds of Challenge 37 C.F.R. 42.104(b)(2) Petitioner requests cancellation of the challenged claims under the following statutory grounds: Ground 1 Claims 31, 32, and 36-38 are anticipated by De Kok (Ex. 1003) under 35 U.S.C. 102(e). Ground 2 Claims 31-38 are obvious over Beasley (Ex. 1004) in view of Timoshin (Ex. 1005) under 35 U.S.C. 103(a). Ground 3 Claims 31-38 are obvious over Beasley (Ex. 1004) in view of Edington (Ex. 1006) under 35 U.S.C. 103(a). Pursuant to 37 C.F.R. 42.204(b)(4), an explanation of how claims 31-38 of the 981 patent are unpatentable under the statutory grounds identified above, that the Petitioner has at least a reasonable likelihood of prevailing on these grounds, including the identification of where each element of the claim is found in the prior art, is provided in Section VIII, below, in the form of claims charts. Pursuant to 37 C.F.R. 42.204(b)(5), the exhibit numbers of the supporting evidence relied upon to support the challenges and the relevance of the evidence to the challenges raised, including identifying specific portions of the evidence that support the challenges, are provided in Section VIII, below, in the form of claim charts. V. THE 981 PATENT A. Overview of the 981 Patent As noted above, the 981 patent employs the commonly used technique known 11

as simultaneous shooting, in which multiple seismic energy sources are fired simultaneously or near-simultaneously. The recorded data contains interference because the shots overlap with one another, resulting in mixed data that includes reflections from each fired source. In order to obtain useful information from the recorded data, one must separate out the data received from each individual source. With proper separation, simultaneous shooting allows for greater shot density, i.e., more shots during a given survey duration, which results in more robust seismic data. The 981 patent proposes to separate recorded signals by time encoding the signals as they are generated. In particular, the 981 patent discloses firing a first source, making a recording of the signal detected by the sensors that is indexed to a known time reference with respect to time of firing the first source, firing a second source at a known, selected time delay after the firing of the first source, while signal recording continues. (Ex. 1001, 5:61-64.) The 981 patent defines a firing sequence as firing the first source, waiting the predetermined delay and firing the second source thereafter. (Ex. 1001, 5:65-6:2.) The 981 patent discloses that the firing sequence, and contemporaneous signal recording, are repeated in a second firing sequence. (Ex. 1001, 6:2-4.) The second firing sequence includes firing the first source, waiting a different selected time delay and then firing the second source, while recording seismic signals. (Ex. 1001, 6:4-7.) The known, selected time delay between firing the first source and firing the second source is different for each successive firing sequence. (Ex. 1001, 6:7-9.) 12

B. Prosecution History of the 981 Patent During prosecution, in an attempt to distinguish the pending claims from the prior art, the Applicant emphasized the importance of varying time delays by stating that [a]n important element of the Applicant s invention is that a time interval between firing the first source and firing the second source is varied between successive ones of the firing sequences. (Ex. 1007, at 31.) Applicant explained that varying the time delays was an advantage because the detected seismic signals can be identified with respect which caused the particular events in the detected seismic signals. (Ex. 1007, at 31.) VI. CLAIM CONSTRUCTION In an inter partes review, claim terms in an unexpired patent are interpreted according to their broadest reasonable interpretation ( BRI ) in view of the specification in which they appear. 37 C.F.R. 42.100(b); Office Patent Trial Practice Guide, 77 Fed. Reg. 48,756, 48,766 (Aug. 14, 2012). In determining the BRI, claim terms receive their ordinary and customary meaning as would be understood by one of ordinary skill in the art in the context of the entire disclosure. In re Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007). The USPTO requires BRI, as the patentee is given opportunity to amend their claims in this proceeding. See, e.g., Office Patent Trial Practice Guide, 77 Fed. Reg. 48,764 (Aug. 14, 2012). As required by these rules, this Petition applies the BRI of claim terms, although BRI may be, and often is, different from a claim construction in 13

district court. See, e.g., In re Trans Texas Holdings Corp., 498 F.3d 1290, 1297 (Fed. Cir. 2007). Thus, the claim interpretations presented in this Petition, including where Petitioner does not propose an express construction, do not necessarily reflect the claim constructions that Petitioner believes should be adopted by a district court under Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005). A. wavelet time This phrase appears in claim 35. Claim 35 recites the delay is at least as long as a wavelet time of the first source. Although the specification of the 981 patent uses the phrase wavelet time, a wavelet is not clearly defined in the 981 specification. For example, the 981 patent states [a]lthough the time delay varies from sequence to sequence, the time delay between firing the first source and the second source in each firing sequence is preferably selected to be at least as long as the wavelet time of the seismic energy generated by the first source to avoid interference between the first and second sources. As discussed in the Ikelle declaration, one having ordinary skill in the art at the time of the earliest filing date claimed by the 981 patent would understand the phrase wavelet time to mean the duration of the source signature. (Ex. 1002, 61-62.) The specification of the 981 patent indicates that time delays at least as long as the wavelet time should be used to avoid interference between the sources. By waiting the duration of the source signature, this interference between the source signatures 14

would be avoided. Only the interference between the reflected wavefields would remain to be decoded. As noted by Dr. Ikelle, a person of ordinary skill in the art would understand that it is incredibly difficult to decode simultaneous shooting data when the source signatures interfere. (Ex. 1002, 63.) Accordingly, the broadest reasonable interpretation of the phrase wavelet time is the duration of the source signature. VII. LEVEL OF ORDINARY SKILL IN THE ART The level of ordinary skill in the art is evidenced by the prior art. See In re GPAC Inc., 57 F.3d 1573, 1579 (Fed. Cir. 1995) (determining that the Board did not err in adopting the approach that the level of skill in the art was best determined by references of record). The prior art discussed herein, and in the declaration of Dr. Ikelle, demonstrates that a person of ordinary skill in the art, at the time the 981 patent was filed, was an engineer, seismologist, or technical equivalent, experienced in seismic data acquisition systems, aware of various aspects of seismic acquisition and seismic data processing pertaining to land or marine seismic surveys. (Ex. 1002, 57-59.) VIII. IDENTIFICATION OF HOW THE CHALLENGED CLAIMS ARE UNPATENTABLE - 37 C.F.R. 42.104(B)(4)-(5) AND 42.22(A)(2) Petitioner provides in the following discussion and claim charts a detailed comparison of the claimed subject matter and the prior art specifying where each element of the challenged claims are found in the prior art references. 15

A. Claims 31, 32, and 36-38 are anticipated by De Kok De Kok discloses time delay encoding techniques which rely both on programmed time delays in the field and polarity decoding in the processing center. In this respect, the technique disclosed in De Kok is more sophisticated than the basic time delay encoding disclosed in the 981 patent. However, even though the 981 patent does not disclose polarity decoding in the processing center, claims 1, 2, 7, and 10-21 of the 981 patent do not exclude an additional step of polarity decoding in the processing center. As such, at least under the broadest reasonable interpretation standard that must be applied in this proceeding before the Board, claims 1, 2, 7, and 10-21 of the 981 patent encompasses the technique disclosed in De Kok. Referring to a standard airgun, the far field source signature is composed of a positive pressure pulse followed by a negative pulse from the sea surface reflection. (Ex. 1003, 3:54-57.) The negative pulse, called the ghost, is time separated from the positive pulse by a time shift that may be referred to as the ghost time delay. (Ex. 1003, 3:57-59.) Figure 2 of De Kok, reproduced below, shows the sequences of two sources firing simultaneously with polarity coding. (Ex. 1003, 4:28-29.) Figure 2 shows a source vessel 201 towing sources 203 and 205. (Ex. 1003, 4:32-33.) A source vessel 201 may also tow a streamer containing sensors for receiving source signals, for example streamer 207. (Ex. 1003, 4:33-35.) In Figure 2, Source 203 emits S1, in which positive (P) and negative (N) polarity source signals alternate as depicted by the 16

positive and negative polarity representation through time. (Ex. 1003, 4:35-38.) Source 205 emits positive signals S2 only. (Ex. 1003, 4:42.) Figures 5-7 of De Kok depict embodiments that include time delay encoding. As noted above, De Kok discloses that the time delay encoding technique relies on programmed time delays in the field and polarity decoding in the processing center. (Ex. 1003, 5:66-6:2.) According to De Kok, the enhancement of data pertaining to a particular desired source is accomplished through equalizing the polarity of corresponding signal components and to align and average (mix or stack) the responses. (Ex. 1003, 6:2-4.) This principle is illustrated with the impulse response representations of FIG. 5A for a marine application, reproduced below. 17

Most notably, in FIG. 5A, Source TD1 and Source TD2, which are sequential series of simultaneous shots, have different delay codes for successive shots (numbered 1 to 4 for each simultaneously activated source). (Ex. 1003, 6:17-21.) The time delays in these figures are relative to an arbitrary reference, here labeled t r =0, represented by the vertical dashed lines. (Ex. 1003, 6:21-23.) For example, simultaneously fired shot 1 from TD1 (501) and shot 1 of TD2 (511) are initiated with no relative time delays between them, but shot 2 from TD2 (513) is initiated before shot 2 of TD1 (503), the time separation between the initiation of shot 2 of TD2 (513) relative to shot 2 of TD1 (503) being the time delay determined or chosen for the acquisition program, which may be for example, the ghost delay. (Ex. 1003, 6:23-30.) 18

Thus, De Kok fully anticipates several of the claims of the 981 patent, as the process disclosed in De Kok includes varying a time interval between firing a first source and a second source between successive ones of firing sequences. The following claim chart illustrates how De Kok meets all of the elements of claims 31, 32, and 36-38 of the 981 patent. 981 Patent Claims De Kok (Ex. 1003) 31.a. A method for determining signal components attributable to a first seismic energy source and to a second seismic energy source in signals recorded from seismic sensors, Ex. 1003 at 3:38-39: The present invention is a method for acquiring seismic data using simultaneously activated seismic energy sources. Ex. 1003 at 4:32-35: FIG. 2 shows a source vessel 201 towing sources 203 and 205. A source vessel 201 may also tow a streamer containing sensors for receiving source signals, for example streamer 207. 31.b. the first and second sources and the sensors towed along a survey line, Ex. 1003 at Fig. 2. Ex. 1003 at 5:23-24: FIG. 4 depicts a four source (203, 205, 413, 415) shooting arrangement with two receiver cables (407, 409). 19

981 Patent Claims De Kok (Ex. 1003) 31.c. the first source and the second source fired in a plurality of sequences, Ex. 1003 at Fig. 4. Ex. 1003 at 5:23-24: FIG. 4 depicts a four source (203, 205, 413, 415) shooting arrangement with two receiver cables (407, 409). Ex. 1003 at Fig. 4. 31.d. a time delay between firing the first source and the second source in each firing sequence being different than the time delay in other ones of the firing sequences, the method comprising: Ex. 1003 at 5:36-39: In the configuration of FIG. 4 the two sources 203 and 205 preceding streamers 407 and 409 are relatively close to each other, and also sources 413 and 415 at the back of the streamers 407 and 409 are in relatively close proximity. Ex. 1003 at 6:18-23: In FIG. 5A, Source TD1 and Source TD2, being sequential series of simultaneous shots, have different delay codes for successive shots (numbered 1 to 4 for each simultaneously activated source). The time delays in these figures are relative to an arbitrary reference, here labeled tr=0, represented by the vertical dashed lines. 20

981 Patent Claims De Kok (Ex. 1003) 31.e. determining a first component of the recorded signals that is coherent from shot to shot and from trace to trace; 31.f. time aligning [the] recorded signals with respect to a firing time of the second source in each firing sequence; and Ex. 1003 at Fig. 5A. Ex. 1003 at 4:47-55: The seismic energy returned from shot records containing multiple source position energy must be separated into source records containing energy responsive to the individual seismic sources. The separation of individual source contributions into source records (as opposed to shot records) is achieved during processing, preferably in the common mid-point (CMP) domain but any other domain where the contributions from successive shot records are present may be used. Ex. 1003 at 6:41-48: Here the result of polarity decoding to enhance and separate energy for the Source TD1 shot series from the shot series of Source TD2 consists of reversing the contributions from shot 3 (505, 515) and shot 4 (507, 517), which causes energy from Source TD1 to reinforce and that of Source TD2 to cancel after mixing, K-filtering or stacking (also here the CMP gather may be the preferred domain to execute the source discrimination). The polarity decoding technique is a form of time- 21

981 Patent Claims De Kok (Ex. 1003) alignment because the polarities are a direct function of the time delays. Decoding the polarities such that the polarities for one source stack while the polarities for the other sources cancel necessarily requires timealignment. (Ex. 1002, 100-102, 129.) 31.g. determining a second component of the signals that is coherent from shot to shot and from trace to trace in the time aligned signals. 32. The method as defined in claim 31 wherein the delay between firing the first source and firing the second source is varied systematically between each firing sequence. 36. The method as defined in claim 31 wherein the determining the first component comprises performing a common mid point gather with respect to the first source of the recorded signals. 37. The method as defined in claim 31 wherein the determining the second Ex. 1003 at 4:47-55: The seismic energy returned from shot records containing multiple source position energy must be separated into source records containing energy responsive to the individual seismic sources. The separation of individual source contributions into source records (as opposed to shot records) is achieved during processing, preferably in the common mid-point (CMP) domain but any other domain where the contributions from successive shot records are present may be used. Ex. 1003 at 5:67 6:1: The time delay encoding technique relies on programmed time delays in the field.... Ex. 1003 at 6:2-4: The time shifts for encoding may be arbitrarily chosen per source, but they should preferably be equal to the ghost time delay in the marine case. Ex. 1003 at 4:47-55: The seismic energy returned from shot records containing multiple source position energy must be separated into source records containing energy responsive to the individual seismic sources. The separation of individual source contributions into source records (as opposed to shot records) is achieved during processing, preferably in the common mid-point (CMP) domain but any other domain where the contributions from successive shot records are present may be used. Ex. 1003 at 4:47-55: The seismic energy returned from shot records containing multiple source position energy must be separated into source 22

981 Patent Claims De Kok (Ex. 1003) component comprises performing a common mid point gather with respect to the second source of the time aligned signals. 38. The method as defined in claim 31 wherein the recorded seismic signals comprise components attributable to at least one additional seismic energy source fired after an additional time interval after the firing the second source in each firing sequence, the additional time interval being different in each sequence, the additional time interval being different from the time delay between firing the first and second source in each sequence, records containing energy responsive to the individual seismic sources. The separation of individual source contributions into source records (as opposed to shot records) is achieved during processing, preferably in the common mid-point (CMP) domain but any other domain where the contributions from successive shot records are present may be used. Ex. 1003 at 7:11-13: In FIG. 7A and FIG. 7B three sources without ghosts are shown. All three sources have different amplitude and have been coded using different time delays. Ex. 1003 at 5:6:53-58: When using a sequence of four shots as in FIG. 5A and FIG. 5B, the method can accommodate three different sources. The coding of a third source, Source TD3, is shown in FIG. 6A and FIG. 6B and consists of positive delay times for shot 1 (601) and shot 4 (607) with negative relative delay times for shot 2 (603) and shot 3 (605). Ex. 1003 at Fig. 6A, 6B. 23

981 Patent Claims De Kok (Ex. 1003) the method further comprising, time aligning the recorded signals with respect to a firing time of the at least one additional source, and determining trace to trace and shot to shot coherent components of the signals Ex. 1003 at 6:41-48: Here the result of polarity decoding to enhance and separate energy for the Source TD1 shot series from the shot series of Source TD2 consists of reversing the contributions from shot 3 (505, 515) and shot 4 (507, 517), which causes energy from Source TD1 to reinforce and that of Source TD2 to cancel after mixing, K-filtering or stacking (also here the CMP gather may be the time aligned with respect to preferred domain to execute the source the firing time of the at least discrimination). one additional source. B. Claims 31-38 are obvious in view of the combined teachings of Beasley and Timoshin 1. The proposed grounds based on Beasley and Timoshin are not redundant to the grounds based on De Kok. The grounds raised in the following sections based on the combined teachings of Beasley and Timoshin are meaningfully distinct from the grounds raised above based on De Kok. Beasley, unlike De Kok, does not explicitly disclose polarity encoding for simultaneous source activation, but more generally discloses that any desired type of encoding could be used for simultaneous or near simultaneous source activation across both the marine and land survey contexts. Timoshin discloses one such type of encoding that was known more than a decade prior to the earliest filing date claimed by the 981 patent a time delay encoding that more closely matches the type of time delay encoding disclosed in the 981 patent than the time delay/polarity encoding/decoding disclosed in De Kok. Specifically, Timoshin discloses using random numbers as launch delays during overlapping source activations. (Ex. 1005, 24

p. 5.) During processing, the results of the effect from a single shot source are summed in phase, while those from different sources are summed out of phase, as the firing delays of the sources are random and independent. (Ex. 1005, p. 5.) Timoshin further discloses that, because of the incoherence of the summation of the wave fields, it is possible to separate the wave fields from different sources during data processing by the common-depth-point method and by constructing seismic images by the diffraction method. (Ex. 1005, p. 7.) As such, the grounds raised in the following sections based on the combined teachings of Beasley and Timoshin are meaningfully distinct from and are not redundant to the grounds raised above based on De Kok. 2. Claim 31 Beasley is directed to marine seismic surveys that include firing seismic sources simultaneously or near simultaneously in which the sources may be arranged to emit encoded wavefields using any desired type of coding but does not explicitly disclose the type of time encoding claimed in the 981 patent. (Ex. 1004, 7:54-56.) While Beasley discusses the use of source encoding in the marine context, it discloses that the same encoding techniques could be used in land seismic surveys. (Ex. 1004, 9:39-44.) Additionally, as Professor Ikelle explains, prior to the 981 patent it was already commonplace to adapt land solutions to marine problems due to the clear relationship between land and marine seismic surveying. (Ex. 1002, 28-31.) For example, the 25

World Oil article makes no distinction between land and marine seismic surveying when discussing using a CMP gather to increase the signal to noise ratio when processing and summing traces. (Ex. 1008, at 86.) Therefore, when assessing what types of encoding techniques could be employed in marine surveying, one of ordinary skill in the art would have known to look to what was being used in land seismic surveying. (Ex. 1002, 149-150.) Timoshin, which issued more than a decade before the 981 patent was filed, discloses the use of time encoding and time alignment to separate sources. (Ex. 1005, p. 7, 2.) Timoshin discloses that by varying the launch delays of overlapping sources based on random numbers, it becomes possible to separate the wave fields from different sources during data processing by the common-depth-point method and by constructing seismic images by the diffraction method. (Ex. 1005, p. 7.) Accordingly, Beasley discloses it is desirable to employ signal encoding techniques, and Timoshin discloses one such known technique. The combination of the known time-encoding technique of Timoshin with the known marine survey technique disclosed in Beasley would do no more than yield the predictable result of making it possible to separate the wave fields from different sources of Beasley during data processing by the common-depth-point method and by constructing seismic images by the diffraction method, as disclosed in Timoshin. (Ex. 1002, 151.) As such, it would have been obvious to employ the known time encoding techniques disclosed in Timoshin in the marine survey of Beasley. (See KSR 26

Int'l Co. v. Teleflex, Inc., 550 U.S. 398, 416 (2007) ( The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results. ).) Furthermore, both Beasley and Timoshin deal with simultaneous shooting, encoding, and decoding. As Dr. Ikelle notes, these similarities would have been enough to motivate a person of ordinary skill to combine Beasley and Timoshin, especially given the natural fit between teachings in Beasley and Timoshin. (Ex. 1002, 148-150.) The following claim chart specifies where each element of claim 31 is found in the combined teachings of Beasley and Timoshin: 981 Patent Claims Beasley (Ex. 1004) and Timoshin (Ex. 1005) 31.a. A method for determining signal components attributable to a first seismic energy source and to a second seismic energy source in signals Ex. 1004 at 1:19-25: The present invention, in certain aspects, is directed to seismic survey systems and methods in which two or more seismic sources are fired simultaneously, or significantly close together temporally, but which is, in one aspect, significantly spatially separated, and resulting seismic recorded from seismic data is processed meaningfully utilizing data sensors, generated by both (or more) seismic sources. 31.b. the first and second sources and the sensors towed along a survey line, Ex. 1004 at 5:68 6:12: FIG. 4 is a plan view of a 3- D swath 13 of six parallel seismic cable arrays A1-A6 which are being towed through a body of water by a ship 14.... A discrete acoustic source SL is towed by ship 14 near the leading end of swath 13, substantially at the center of the swath. Ex. 1004 at 6:48-51: A second ship 24, towing an acoustic source ST launches a wavefield from the trailing end of swatch 13. 27

981 Patent Claims Beasley (Ex. 1004) and Timoshin (Ex. 1005) 31.c. the first source and the second source fired in a plurality of sequences, 31.d. a time delay between firing the first source and the second source in each firing sequence being different than the time delay in other ones of the firing sequences, the method comprising: 31.e. determining a first component of the recorded signals that is coherent from shot to shot and from trace to trace; Ex. 1004 at Fig. 4 (ST, ST ). Ex. 1004 at 8:4-11: Timer 26 causes sources SL and ST to launch a first and a second acoustic wavefield in alternate cycles in accordance with the timing diagram shown in FIG. 8. Assuming that source SL is first activated at time T 0 and thereafter repeatedly activated at timed intervals until time T n, source ST is activated at time t 0 after a time shift through delay line 29 of half an interval and thereafter repeatedly activated until time interval t n. Ex. 1005 at page 5: A sequence of P random numbers is generated for each position of the receiving device and a series of P excitation points. They are bounded on one side by the correlation radius of seismograms obtained from the different excitation points, and the other by on-half of the seismogram s duration. These random numbers are used as launch delays for sources positioned at P excitation points while the seismic waves from all these sources are recorded continuously. Launch times of the sources are stored in the memory and are used for the separation of the wave fields in processing the results. In performing summation by using the multifold reflection technique, the signals from one excitation source are summed in-phase, while those from different sources out-of-phase, since the launch delays of the sources are random and independent. Ex. 1005 at page 5: A sequence of P random numbers is generated for each position of the receiving device and a series of P excitation points. They are bounded on one side by the correlation radius of seismograms obtained from the different 28

981 Patent Claims Beasley (Ex. 1004) and Timoshin (Ex. 1005) excitation points, and the other by on-half of the seismogram s duration. These random numbers are used as launch delays for sources positioned at P excitation points while the seismic waves from all these sources are recorded continuously. Launch times of the sources are stored in the memory and are used for the separation of the wave fields in processing the results. In performing summation by using the multifold reflection technique, the signals from one excitation source are summed in-phase, while those from different sources out-of-phase, since the launch delays of the sources are random and independent. 31.f. time aligning [the] recorded signals with respect to a firing time of the second source in each firing sequence; and 31.g. determining a second component of the signals that is coherent from shot to shot and from trace to trace in the time aligned signals. Ex. 1005 at page 5: A sequence of P random numbers is generated for each position of the receiving device and a series of P excitation points. They are bounded on one side by the correlation radius of seismograms obtained from the different excitation points, and the other by on-half of the seismogram s duration. These random numbers are used as launch delays for sources positioned at P excitation points while the seismic waves from all these sources are recorded continuously. Launch times of the sources are stored in the memory and are used for the separation of the wave fields in processing the results. In performing summation by using the multifold reflection technique, the signals from one excitation source are summed in-phase, while those from different sources out-of-phase, since the launch delays of the sources are random and independent. Ex. 1004 at 11:6-9: In the CMP Sort step, individual data traces are sorted into those that share common midpoints to make each trace distinct and can be discriminated e.g. so that move out is hyperbolic and distance from other source data. (See also Ex. 1004, 4:6-29; Fig. 14; 10:11-15; 11:6-9.) 29

3. Claim 38 Claim 38 depends from claim 31 and further recites the recorded seismic signals include components attributable to at least one additional seismic energy source fired after an additional time interval after the firing the second source in each firing sequence. The additional time interval is different in each sequence, and the additional time interval is different from the time delay between firing the first and second source in each sequence. Claim 38 further recites time aligning the recorded signals with respect to a firing time of the at least one additional source, and determining trace to trace and shot to shot coherent components of the signals time aligned with respect to the firing time of the at least one additional source. Beasley discloses using three or more sources in a shot sequence, stating [i]t is within the scope of this invention for there to be any number of source firings from one to several hundred or more Alternatively, one vessel may tow multiple seismic sources or each of two or more vessels may each tow two or more sources. (Ex. 1004, 8: 47-56, emphasis added.) Further, for at least the same reasons discussed above with respect to claim 31, it would have been obvious prior to the earliest filing date claimed by the 981 patent to: (a) make the additional selected time interval different than the time interval between firing the first and second sources, (b) vary the additional time interval between successive ones of the firing sequences, (c) time align the recorded signals, and (d) determine trace to trace and shot to shot coherent components of the signals time aligned with respect to the firing time of the at least 30

one additional source. In particular, such a technique is one known method of encoding signal sources and it would have been obvious to apply this known technique to any number of sources used in the method of Beasley to achieve the predictable result of signal that are encoded based on firing timing. Accordingly, claim 38 is obvious in view of the combined teachings of Beasley and Timoshin. 4. Claims 32-35. Claims 32-35 each directly depend from claim 31 and recite aspects of how the time interval between firing the first source and the second source are varied. As discussed above, the art cited herein establishes that varying such time intervals was old and well known long before the earliest filing date claimed by the 981 patent. a. Claim 32. Claim 32 depends from claim 31 and recites the time interval is varied systematically. Once one of ordinary skill selects the known source signal encoding option of time interval variation, selecting the time intervals at random, pseudorandomly, or based on a predetermined correlation were all obvious variants, the selection of which was well within the skill of one having ordinary skill in the art prior to the earliest filing date claimed by the 981 patent. (Ex. 1002, 164, 225.) Accordingly, claim 32 would have been obvious in view of the combined teachings of Beasley and Timoshin. 31

b. Claim 33. Claim 33 depends from claim 32 and recites the time interval is varied quasirandomly. Once one of ordinary skill selects the known source signal encoding option of time interval variation, selecting the time intervals at random, pseudorandomly, or based on a predetermined correlation were all obvious variants, the selection of which was well within the skill of one having ordinary skill in the art prior to the earliest filing date claimed by the 981 patent. (Ex. 1002, 166, 226.) Accordingly, claim 33 would have been obvious in view of the combined teachings of Beasley and Timoshin. c. Claim 34. Claim 34 depends from claim 32 and recites the time interval varied is randomly. Timoshin explicitly discloses using random numbers for the firing delays. (Ex. 1005, Abstract.) Accordingly, claim 34 would have been obvious in view of the combined teachings of Beasley and Timoshin. d. Claim 35. Claim 35 depends from claim 32 and recites the time interval is at least as long as a wavelet time of the first source. Given the use of time delay encoding, it would have been obvious to a person of ordinary skill in the art to use time intervals that was at least as long as the wavelet time of the first source. Dr. Ikelle states that a person of ordinary skill in the art would understand the advantage of waiting at least the wavelet time is that it prevents the source signatures from interfering. The 32

interference of source signatures greatly hinders attempts to separate the data and thus it would be obvious to a person of ordinary skill to avoid this interference by waiting at least the wavelet time of the first source. (Ex. 1002, 61-63, 173, 228.) 5. Claims 36 and 37. Claims 36 and 37 each depend from claim 32. Claim 36 recites the determining the first component comprises performing a common mid point gather with respect to the first source of the recorded signals. Claim 37 recites the determining the second component comprises performing a common mid point gather with respect to the second source of the time aligned signals. A CMP gather is a collection of all the data with respect to a particular subsurface location. More specifically, a CMP gather constitutes all the traces for which the midpoint between a given source and receiver is the same, which correspond to the same set of reflections being detected. 33

The figure above shows the common midpoints between a number of sources and receivers. With multiple sources and receivers at different locations, there is a common midpoint between different source-receiver pairs. A CMP gather involves collecting the traces that result from reflections off this common location which improves the signal to noise ratio of the data. (Ex. 1002, 30.) Not surprisingly, Beasley does not waste text explaining these basic techniques for sorting data, instead referring to them as known : To separate the sources' data, the record is updated with one source's geometry information (e.g. x, y location coordinates and time of day identifiers, e.g. SEG standard format information, are attached to the seismic data traces by known methods, e.g. a header with the desired information is applied to a trace tape); optionally sorted to order, e.g. by known common mid-point (CMP) sorting methods or known methods such as common shot order, common detector order or common offset order and/or combinations thereof; optionally trace interpolated to theoretically produce a well-sampled curve between known data points by known methods, and spatially paneled, i.e., a portion of the data is isolated that includes data from both sources. (Ex. 1004, 4:16-29, emphasis added. See also Ex. 1004, Fig. 14; 10:11-15, FIG. 14 illustrates a portion of the trace data from FIG. 13 by sorting the data according to shared common mid-points by known CMP sorting methods and then selecting two sets of data traces from the sorted data, the sets designated as Panel A and Panel B. ) 34