N OTE : This disposition is nonprecedential. 

# United States **Court of Appeals**  **for the Federal Circuit**

______________________ NUVASIVE, INC., Appellant

v.

ANDREI IANCU, UNDER SECRETARY OF COMMERCE FOR INTELLECTUAL PROPERTY AND DIRECTOR OF THE UNITED STATES PATENT AND TRADEMARK OFFICE, Intervenor

______________________

2017

- 1666

______________________ Appeal from the United States Patent and Trademark Office, Patent Trial and Appeal Boa rd in No. 95/001,888.

______________________
Decided: November 9, 2018

______________________

M ICHAEL T. R OSATO , Wilson, Sonsini, Goodrich & Rosati, PC, Seattle, WA, argued for appellant. Also represented by S ONJA R OCHELLE G ERRARD ; G RACE J. P AK , P AUL D AVID T RIPODI , II , Los Angeles, CA; R ICHARD T ORCZON , Washington, DC.

B ENJAMIN T. H ICKMAN , Office of the Solicitor, United States Patent and Trademark Office, Alexandria, VA,NUVASIVE , INC

. v. IANCU 2

argued for intervenor. Also represented by T HOMAS W. K RAUSE , F RANCES L YNCH

.

______________________
Before N EWMAN , C HEN , and H UGHES , Circuit Judges.

C HEN , Circuit Judge NuVasive, Inc. (NuVasive) appeals from the decision of the U.S. Patent and Trademark Off ice

, Patent Trial and Appeal Board (Board) in an inter partes reexam in ation proceeding holding claims 17

– 22 and 24

– 27 of U.S. Patent No. 7,691, 057 obvious. The ’057 patent is directed
to a surgical access system and related methods for crea ting minimally invasive operative corridors through tissue with significant neural structures. ’057 patent col. 2 l. 61

– col. 3 l. 7. Because the PTO admits that its constru ction of “lateral, trans

- psoas path to the targeted lumbar spinal disc ” was too broad, we modify its construction to align with the construction we adopted in In re NuVasive, Inc. , 693 F. App’x 893 (Fed. Cir. 2017) ( NuVasive I ) for a
very similar term. As to secondary considerations , we conclude that the Board erred in finding n o nexus b etween NuVasive’s claimed method and its commercial

“ eXtreme Lateral Interbody Fusion ” (XLIF) surgical technique

. And we conclude that further fact finding is needed as to whether WIPO Publication No. WO 01/37728 (Kelleher) teaches a nerve

- monito ring technique for the ili ohypogastric and ilio i nguinal nerves. Accordingly, we vacate the Board’s obviousness determination and r emand for the Board to conduct a new analysis consistent with this opinion.

B ACKGROUND
A Interbody fusion is a commonly use d surgical proc edure to address pain associated with damaged intervert ebral discs. The procedure involves removing some or all ofNUVASIVE , INC

. v. IANCU 3

a damaged disc and inserting an implant in place of the disc. There are three primary approaches to this spinal
surg ical are a : posterior, anterior, and lateral. While the lateral approach (from the side of the patient’s body) provides the most direct route to the disc space, one major obstacle is the lumbar plexus, a network of nerves orig inating in the spinal column and exit ing through the opening of the lumbar vertebra. The lumbar plexus runs through the psoas muscle and is found in the poste rior portion of the muscle. The nerves of the lumbar plexus innervate ( i.e.

, supply) the leg and pelvic region with

sensor y and motor neurons. Surgery through the lumbar plexus is challenging because the nerves are anatomically tethered to the spinal column so they cannot be easily moved out of the surgical path. And damage to the nerves in the lumbar plexus can have serious side effects

, inclu ding motor function impairment and extreme pain

. As a result, before the patented method, surgeons traditionally performed interbody fusion procedures from the posterior aspect (back) or anterior aspect (front) of a patient. These approaches, however, also had their drawbacks. The posterior approach required removing the bony pro cesses from the spine and wa s associated with a higher incidence of neural complications from damage to the paraspinal nerves emanating from the rear of the spinal column. The anterior approach r isked da maging internal organs and major blood vessels.

NuVasive’s ’057 patent addressed these challenges by making a lateral approach through the psoas muscle safer. NuVasive markets this trans

- psoas surgical syst em and procedure under the tradename “eXtreme Lateral Interbody Fusion” or “XLIF.” The ’057 patent, entitled “Surgical Access System and Related Methods,” covers a surgical access system and related methods for creati ng a minimally invasive oper ative cor ridor through tissue with significant neural stru c-NUVASIVE , INC

. v. IANCU 4

tures

. ’057 patent col. 2 l. 61

– col. 3 l. 7. This access

sy stem and related method involve: (1) distracting the tissue between the patient’s skin and surgical target site to create a distraction corridor, (2) retracting the distra ction corridor to establish and maintain an operative corridor, and (3) detecting the existence of neural stru ctures before and during the establishment of the oper ative corridor. Id . at col. 3 ll. 8– 19. Nerve

- monitoring ( i.e.

, electromyography (EMG) ) i s accomplished with electrodes attached to the instruments used to create the operative corridor. Id . at col. 12 ll. 17

– 52. These electrodes emit a charge as the instruments advance through the body. Id

. When the charge reaches a nerve, the nerve stimulates the muscle group it controls, and a surgeon observes the associated muscle twitch

. Id . This mu scle twitch data can also be fe d into a graphical user interface that di splays information about an instru ment’s direction and relation relative to nearby nerves. Id

. Claim 17, from which all of the challenged claims d epend, covers NuVasive’s surgical access system and related methods. It reads : A method of accessing a surgical target site within a spine, comprising the steps of: (a) creating a distraction corridor along a la teral, trans

- psoas path to a targeted lumbar spinal disc in a lumbar spine using a distraction asse mbly comprising at least two dilators that are s equentially inserted along the later al, trans

psoas path to the targeted lumbar spinal disc , and performing neuromonitoring during at least a portion of the time the distraction asse mbly is used in creating the distraction corridor along the lateral, trans

- psoas path , wherein the neuromonito ring comprises causing the emi ssion of a plurality of electrical stimulation signals from a stimulation electrode provided on a distalNUVASIVE , INC

. v. IANCU 5

portion of at least one component of the distra ction assembly and monitoring for resulting ele ctromyographic (EMG) activi ty after the emission of each stimulation signal, and wherein the co mponent of the distraction assembly is coupled to a control unit of a neuromonitoring system that is capable of displaying to a user an indication of at least one of proximity and directio n of a nerve to the stimulation electrode provided on the comp onent of the distraction assembly based on the monitored resulting electromyographic (EMG) a ctivity; (b) slidably advancing a plurality of retractor blades of a retraction assembly along an out e rmost dilator of the at least two dilators of the di straction assembly, the retraction assembly comprising a handle assembly coupled to the pl urality of retractor blades such that the retractor blades extend generally perpendicularly relative to arm porti ons of the handle assembly, each of said plurality of retractor blades having a genera lly concave inner face and a generally convex ext erior face, said handle assembly being capable of moving said plurality of retractor blades from a closed position to an open position, said closed p osition being characterized by said plurality of r etractor blades being positioned to abut one another and form a closed perimeter, said open position characterized by said plurality of retra ctor blades being positioned generall y away from one another and forming an open perimeter; (c) simultaneously introducing said plurality of retractor blades over the outermost dilator of said distraction assembly along the lateral,
trans

- psoas path to the targeted lumbar sp inal disc while i n said closed position;NUVASIVE , INC

. v. IANCU 6

(d) actuating said handle assembly to move said plurality of retractor blades to the open pos ition so that the plurality of retractor blades create an operative corridor along the lateral, trans

psoas path to the targeted lumbar sp inal disc; (e) releasably engaging a fixation element with at least one of the plurality of retractor blades so that a distal portion of the fixation el ement extends distally from the at least one retra ctor blade and penetrates into a lateral aspect of th e lumbar spine, wherein the fixation element secures the at least one retractor blade to the lumbar spine; (f) inserting an implant through the operative corridor created by the plurality of retractor blades along the lateral, trans

- psoas path to the targeted lumbar spinal disc

. Id . at col. 16 l. 28

– col. 17 l. 3 (emphases added)

. Like the method claimed in the ’057 patent, NuV asive’s XLIF procedure involves inserting an implant through a t rans

- psoas operative corridor. The operative corridor is created by inserting sequential dilators along a lateral trans

- psoas path to the lumbar spine. A retractor instrument is then advanced over the last inserted dil ator, and a fixation element is engaged to maintain the operative corridor. During this process, EMG electrodes mounted on the surgical instruments and connected to NuVasive’s Neuro Vision ® System allow s surgeons to monitor the placement of the surgical instruments rel ative to nearby neural structures.

B

NuVasive sued Globus Medical, Inc. for infringement of the ’057 patent on October 5, 2010 , and Globus filed a

req uest for an inter partes reexamination on February 8,NUVASIVE , INC

. v. IANCU 7

2012 , relying on several prior art references

. The Exa miner ordered a reexamination on claims 17

– 22 an d 24

– 27.

1. Prior Art

Kossmann 1 describes establishing a narrow operative corridor from the side of the patient’s body to repair injuries to the spine

. After making an incision, surgeons used a table

- fixed retractor system to open the path to the affected vertebra. “To reach the vertebral bodies of the lumbar spine, the psoas muscle was mobilized at least in part and pushed backwards to reach the lateral aspect of the vertebra.

. . . Splittin g of the psoas muscle along its fibers had to be done in very athletic patients, since the excessive size of the muscle did not allow a direct lateral access to the vertebra.” J .A. 1263 6. This splitting was performed using a “blunt dissection” technique involving the surgeon’s finger or a wet sponge mounted on a stick to

care fully separate the tissue. J.A. 12635

– 36.

Branch 2 discloses using a retractor for creating surg ical access channels and specifically contemplates inte rbody fusion and disc replacemen t surgeries. ’93 3 patent (Branch) col. 2 ll. 47

– 51. After a surgeon makes an initial incision, she sequentially advances dilators through the incision to gradually widen the space of the operative corridor. Id . Once the operative corridor is the desire d size, the surgeon positions a retractor over the last inser ted dilator to maintain a working channel. Id

.

1 Thomas Kossmann et al., Minimally Invasive Ve rtebral Replacement with Cages in Thoracic and Lumbar Spine , 6 Euro. J. of Trauma 292

– 300 (2001).

2 U.S. Patent No. 6,945,93 3, entitled “Instruments and Methods for Minimally Invasive Tissue Retraction and Surgery.”NUVASIVE , INC

. v. IANCU 8

Koros 3 teaches a variable length retractor designed to “hold organs, muscles, arteries, and other tissue out of the way” during surgery. ’139 pa tent (Koros) col. 1 ll. 34

– 50.

Kelleher 4 describes a system for “detecting the pre sence of a nerve near a surgical tool or probe .” WO 01/37728 (Kelleher) , Abstract

. Kelleher observes that “it is especially important to sense the presence of spinal

nerv es when performing spinal surgery, since these nerves are responsible for the control of major body fun ctions.” Id . at col. 1 ll. 15

– 17. The detection system relies on EMG to detect responses in the muscles controlled by the rele vant nerves. Id

. at col. 10 ll. 7

– 9. The system employs surgical tools with electrified cannuale through which other surgical tools are introd uced into the patient. Id

. at col. 16 ll. 15

– 27. These electrified cannulae emit an electric charge

, which stimulates nerves, and t hese nerves in turn stimulate certain muscle groups to twitch

. Id

. at col. 12 ll. 21

– 34. The relevant muscle groups for lumbar spinal surgery are those in the pa tient’s legs. Id

. at col. 21 ll . 15

– 25. NuVasive is the assignee of the Kelleher applicatio n.
2. First Office Action and Board Decision

In the first office action in the reexamination

, the E xaminer rejected the claim s as obvio us over Kossmann, Branch, Koros, and Kelleher. The Examiner found that Kossmann dis closes a trans

- psoas approach to sp inal surgery; Branch teaches using a series of sequen tial dilators and a retractor assembly for crea ting an oper ative corridor; Koros describes fixation screws that screw into the vertebrae at opposite sides of an affected disc ;

3 U.S. Patent No. 5,928,139, entitled “Retractor with Adjustable Length Blades and Light Pipe Guides.”

4 WIPO Publication No. WO 01/ 37728, entitl ed “Electromyography Systems.”NUVASIVE , INC

. v. IANCU 9

and Kelleher discloses EMG nerve

- monitoring

. Because all these references pertain to minimally invasive surgical tech niques, the Examiner found that it would have been obvious to a skilled artisan to combine them to arrive at the claimed surgical system and related method.

In r esponse, NuVasive presented two theories of no nobviousness and testimony from Dr. Jim Youssef, an orthopedic surgeon , to support these theories

. First, NuVasive argued that none of the prior art taught crea ting an operative corridor along a lateral, trans

- psoas path using dilators and retractors, as recited in the claims of the ’057 patent . Kossmann primarily discussed moving the psoas muscle aside and only mentioned splitting the psoas muscle along its fibers in athletic patients with large psoas muscles. Even in those patients, surgeons split the psoas muscle with blunt dissection (using a finger or sponge on a stick)

, not with dilators and retra ctors. Blunt dissection , NuVasive asserted, was safer than dila tion and retraction be cause surgeons viewed a sponge or finger as a safer tool than a dilator or retractor . Second NuVasive argued that while Kelleher is directed to sy stems for detecting the presence of nerves during surgical procedures, it does not teac h monitoring nerves along a “lateral, trans

- psoas path to the targeted lumbar spinal disc.” J .A. 348. NuVasive also argued that there was no reasoned explanation in the office action or r eexamina tion

r equest to support Globus’s motivation to combine Kell eher with Bran ch, Kossmann, and Koros

. Globus responded with expert testimony from Dr. Isador Lieberman, an orthopedic surgeon specializing in spinal surgery. Dr. Lieberman rejected NuVasive’s theory that “blunt dissection” was safer than using dila tors and
retractors. Dr. Lieberman explained that “both tec hniques do the exact same thing for the exact same pu rpose” and that “one of ordinary skill in the art would have under stood how to penetrate a distractor and retractor assembly through the psoas musc le

. ” J.A. 435

. This isNUVASIVE , INC

. v. IANCU 10

because skilled artisans were familiar with how to split

psoas

- muscle tissue in line with its fibers to minimize damage to the nerves

, and NuVasive’s approach merely used ubiquitous surgical tools such as retractors to do so. Dr. Lie berman also opined that, because “Kelleher di scloses a nerve detection system for use with surgical tools or probes for spinal surgery, one of ordinary skill in the art would understand how to [use it to] achieve an even greater ability to negotiate aro und important neuronal structures during trans

- psoas operations.” J.A. 436. After considering the evidence, the Examiner co ncluded that the challenged claims would not have been obvious. The Examiner found that the prior art did not expressly teach dissection of the psoas muscle using a dilator and retractor , and “Kossman[n] [taught] using a
trans

- psoas approach for only a few patients and even then, using blunt dissection .” J.A. 530

– 31. The Examiner also found that Kelleher did not explicitly teac h usi ng

nerve

- monitoring in the lateral, trans

- psoas context even though Kell eher did teach its use in lumbar spinal su rgery. Globus appealed to the Board.

The Board reversed the Examiner , finding the “blunt

dissection” methods described in Kossmann not meanin gfully different from the ’057 patent’s dilators and retra ctor. Specifically, the Board found that the Examiner “erred in concluding that one of ordinary skill in the art would not have considered the use of a dilator, as taught by Branch, to be an alternative ‘blunt instrument’ suit able for use in a ‘blunt dissection’ of the psoas muscle.” J.A. 955. “Branch evinces that a dilator is an alternative ‘blunt instrument’ that would appear to provide a more precise and gradually increasing pathway as compared to a surgeon’s finger or wet sponge on a stick, as taught by Kossmann.” J.A. 856. The Board also disagreed with the weight the Examiner placed on the fact that Kossmann disclosed only splitting the psoas muscle in very athletic patients. “[A]ny n eed or problem known in the field ofNUVASIVE , INC

. v. IANCU 11

endeavor at the time of the invention and addressed by the patent can provide a reason for co mbining the el ements in the man ner claimed.” KSR Int’l Co. v. Teleflex Inc. , 550 U.S. 398, 420 (2007)

. Thus , the Board dete rmined that the problem of providing a lateral approach in “very athletic patients” is a reason that the skilled artisan would have used a lateral trans

- psoas approach as taught by Kossmann. The Board also disagreed with the Examiner’s fin dings on Kellehe r. T he Board found that it would have be en obvious to a skilled artisan to look to Kelleher’s

nerve

- monitoring system because Branch and Kossmann both teach the desirability of avoiding nerves in spinal surgery, and Kelleher itself discloses use in a mini mally

invasive spinal surgical system.

3. Claim Amendment

The Board’s reversal of the Examiner’s decision crea ted a new ground of r ejection. 37 C.F.R. § 41.77(f) (2016)

. NuVasive chose to reopen prosecution rather than seek reconsideration of the Board ’s decision. NuVasive amended claim 17 to include the use of nerve

- monitoring technology— a limitation already recited in some of the other challenged claims

— and offered objective evidence of nonobviousness supported by the declarations of three witnesses . After NuVasive submitted its new evidence

, and before the Examiner issued the next office action, NuVasive and Globus settled, and Globus ended its participation in the reexamination.

4. Second Board Decision

After the claim amendment , the Examiner on c e a gain found the claims to be non obvious. Specifically, the Examiner found tha t none of the references taught nerve

monitoring during a lateral, trans

- psoas spinal procedure

. For Kelleher to be properly combined with the other references, the Examiner stated that , “Kelleher mustNUVASIVE , INC

. v. IANCU 12

provide some suggestion or teaching to apply the taught neuromonitoring during a lateral trans

- psoas spinal procedure.” J.A. 2801. And Kelleher, the Examiner concluded, does not. Id . The Examiner also found NuV asive’s object ive evidence of nonobviousness persuasive. The Examiner cited an article touting “the use of real

time directional neuromonitoring to ensure a safe p assage through the psoas

- muscle

, ” as “ a feature contributing to the success of the patent under reexamina t ion.” J.A. 2802. Although Globus had ceased its participation in the reexamination proceedings, the Examiner’s patentability decision returned to the Board for review under 37 C.F.R. § 41.77(f). The Board once again reversed the Examiner. In its secon d decision, the Board offered three additional rationales and reiterated its previous reasoning to su pport its obviousness findings.
First, the Board construe d the phrase “lateral, trans

pso as path to the targeted lumbar spinal disc.” J .A. 8– 10. While it previously did not feel the need to construe t he term, the Board found construction necessary after NuV asive introduced objective evidence of nonobviousness. Id

. The Board concluded that the broadest reasonable inte rpretation of the phrase “encompasses a path, to the lu mbar spinal disc, which passes through any portion of the psoas muscle, regardless of the portion, and which is to the lateral side of the body, to any significant degree, as compared to an anterior puncture.” J.A. 10. Second, the Board once again disagreed with the E xaminer that Kelleher must provide some suggestion or teaching to apply neuromonitoring to a lateral trans

psoas spinal procedure. The Board found that Kelleher’s neuromonitoring technology achieves Kossman n ’s and B ranch’s desire to avoid nerves, and Kelleher itself di scloses the use of nerve

- monitoring in a minimally in vasive spinal surgical system. T he Board found that it “is of noNUVASIVE , INC

. v. IANCU 13

moment that the nerves sought to be avoided in Kossmann [‘s lateral approac h] are the iliohypogastric and ilioinguinal nerves [;] these are still nerves that Kossmann teaches should be avoided in a lateral approach .” J.A. 12. While these nerves may not be present in the psoas muscle, both are still part of the lumbar plexus, whi ch the ’057 patented method seeks to avoid

. The Board also rejected NuVasive’s argument that Kossmann only teac hes traversing a “safe zone” of the psoas muscle where the important neural structures do not reside. The ’057 patent does not define any parti cular “lateral, trans

- psoas path to the targeted lumbar spinal disc, ” and the claims themselves do not recite the step of navigating through the lumbar plexus or any particular nerves. Thus even if Kossmann’s lateral trans

- psoas path does not implicate th e majority of the lumbar plexus

, because Kossmann expressly teaches avoiding the iliohypogastric and il ioinguinal nerves, the Board found that no additional nerves need be avoided for th e prior art to suggest that a skilled artisan would be motivated to in clu de a nerve

monitoring step during the creation of the operative corridor.
Third, the Board found that NuVasive’s objective ev idence carried little weight due to a lack of nexus with the challenged claims. “For objective evidence to be accorded substantial weight, its proponent must establish a nexus between the evidence and the merits of the claimed inve ntion.” In re GPAC Inc.

, 57 F.3d 1573, 1580 (Fed. Cir. 1995). In particular, the objective indicia “ must be tied to the novel elements of the claim at issue” and “ be reason ably commensurat e with the scope of the claims. ” Institut Pasteur & Universite Pierre Et Marie Curie v. Focarino

, 738 F.3d 1337, 1347 (Fed. Cir. 2013). The Board conclu ded that NuVasive had failed to prove this nexus based o n two grounds

. U sing its construction of “lateral, trans

psoas path,” the Board noted that claim 17 of the ’057 patent is not limited to the lateral approach used in theNUVASIVE , INC

. v. IANCU 14

XLIF procedure, but instead encompasses any psoas

traversing approach that is lateral to the midl ine to any significant degree. The Board thus found that the XLIF procedure, is not reasonably commensu rate with the scope of the claims. J.A. 19

– 20.

Next , the Board found that NuVasive ’s evidence failed to adequately establish what actuall y comprises the XLIF procedure and whether it is encompassed by claim 17 of the ’ 057 patent. While NuVasive did provide a claim chart mapping the features of claim 17 to its XLIF system and procedure, the Board concluded it was unable to discern whether t he MaXcess ® II Access System and NeuroVision ® System, to which the chart refers, were part of the XLIF system. The Board also noted that NuV asive ’s marketing materials at times used XLIF as a ma rketing term to identify a surgical technique and used XLIF at other times to identify groups of products. The Board concluded that, “when [NuVasive] uses the shor thand term ‘XLIF’ in its Request [to Reopen Prosecution]

, without clarification, we are unable to associate [NuV asive’s] objective eviden ce with particular products or features.” J.A. 18. Thus, while NuVasive presented evidence of long

- felt need, skepticism followed by praise and recognition, and commercial success, the Board was not persuaded by NuVasive’ s evidence due to this lack of

nexus . The Board additionally found NuVasive’s objective evidence of nonobviousness insufficient.
Taking all of the evidence into consideration , the Board concluded that claim 17 as amended

, and the claims that depend therefrom

, would have been obvious. N uVasive appeals the B oard’s second decision under 35 U.S.C. §§ 141 and 142. We have jurisdiction under 28 U.S.C. § 1295(a)(4)(A).NUVASIVE , INC

. v. IANCU 15

D ISCUSSION
A “Obviousness is a question of law based on underlying findings of fact.” In re Kubin , 561 F.3d 1351, 1355 (Fe d. Cir. 2009). We review the Board’s decisions under the standards set forth in § 706 of the Administrative Proc edure Act (APA). We set aside the Board’s decisions if they are “arbitrary, capricious an abuse of discretion, or othe rwise n ot in accordance with law” or “unsupported by substantia l evidence.” 5 U.S.C. § 706(2) (2012)

. We review the Board’s legal conclusions de novo and its factual findings for substantial evidence. In re Gartside

, 203 F.3d 1305, 1316 (Fed. Cir. 2016). A finding of fact is supported by substantial evidence if a reasonable mind might accept the evidence as adequate support for the finding. Consol. Edison Co. v. NLRB , 305 U.S. 197, 229 (1938). “If the evidence in [the] record will support seve ral reasona ble but contradictory conclusions, we will not find the Board’s decision unsupported by substantial evidence simply because the Board chose one conclusion over another plausible alternative. ” In re Jolley , 308 F.3d 1317, 1320 (Fed. Cir. 2002)

. B

NuVas ive presents three primary arguments on a ppeal. First

, NuVasive contends that the Board erred in its construction of the term “lateral, trans

- psoas path to the targeted lumbar spinal disc .” Specifically, NuVasive argues that the Board erred by failing to consider how the term “lateral” was used in the context of the ’057 patent. Second , NuVasive claims the Board erred in disregarding the evidence of secondary considerations by using its overly broad claim construction of “lateral, trans

- psoas path to the targeted lumbar spinal disc” to conclude that the claims were not reasonably commensurate with the objective evidence and that the Board misunderstood the scope of the XLIF procedure

. Third , NuVasive arguesNUVASIVE , INC

. v. IANCU 16

that the Board committed legal error because its obviou sness determination lacks a motivation to combine the prior art references. We address each of these issues in turn below.

C
Because NuVasive’s appeal turns in part on the co nstruction of “lateral, trans

- psoas path to the targeted lumbar spinal disc,” we address the claim construction issue below first.

The Board construed the term “lateral, trans

- psoas path to the targeted lumbar spinal disc” as encompassing “a path to the lumbar spinal disc, which passes through any portion of the psoas muscle, regardless of the portion, and which is to the lateral side of the body, to any significant degree, as compared to an anterior puncture.” J.A. 10

. NuVasive contends that this construction is unre asonably broad, and on appeal, the PTO concedes that the Boar d’s construction might be too broad in light of our opinion in In re NuVasive, Inc. , 693 F. App’x 893 (Fed. Cir. 2017) ( NuVasive I )

. We issued a non

- precedential opinion in NuVasive I shortly after NuVasive filed its notice of appeal in this case. NuVasive I was an appeal from an inter partes review filed by Medtronic, Inc. on U.S. Patent No. 8,01 6 ,767, which shares a very similar specifica tion with the ’05 7 patent. 693 F. App’x at 894

– 95. We concluded there that the broadest reasonable interpreta tion of the phrase “lateral, trans

- psoas path to the lumbar spine ” was “ an approach to the lumbar spine that (1) approaches from the patient’s lateral aspect; and (2) goes through the psoas muscle. ” 693 F. App’x at 900

– 901.NUVASIVE , INC

. v. IANCU 17

In light of the similarities between the ’767 and ’057 patents, 5 and because the parties agree that the appr opr i ate construction of “lateral, trans

- psoas path to the
ta r geted lumbar spinal disc ” is that which we enumerated for “lateral, trans

- psoas path to the lumbar spine” in NuVasiv e I , we adopt that construc tion here. See Oral Arg. 1:33

– 2:00 , 3:57

– 4:19; Intervenor Br. at 33. W e review the Board’s obviousness decision in accordance with that construction below.

D Because this new construction is directly implicated in the Board’s analysis of secondary considerations, we address this issue next. The Board concluded that NuV asive’s evidence of secondary considerations was unpersu asive because NuVasive had failed to establish a nexus between the claim ed invention and the XLIF surgica l technique . The Board provided two separate grounds for its conclusion. Under the first ground, the Board concluded that the XLIF procedure was not reasonably commensurate to the scope of the claims because the claims broadly covered a “lateral, trans -p soas path” that “encompasses a path to

5 The ’057 and ’767 patents both disclose a surgical access system that includes a tissue distraction assembly, a tissue retraction assembly, and nerve

- monitoring. ’057 patent, abstract; ’767 patent, abstract. They also share many similar specification passages as well as figures. Compare ’057 Patent, Figures 2

– 5 and 16

– 18 with ’767 Patent, Figures 9

– 12 and 20

– 22. The fields of invention in both patents are identical, the discussion of the prior art is substa ntially similar, and the surgical systems and related methods described in the preferred embodiments are likewise substantially similar. See ’057 patent col. 1 l. 30

– col. 2 l. 57; ’676 patent col. 1 34

– col. 2 l. 60.NUVASIVE , INC

. v. IANCU 18

the lumbar spinal disc, which passes through any portion of the psoas muscle, regardless of the portion, and which is to the lateral side of the body, to any significant degree, as compared to an anterior puncture.” J .A. 10 , 20. On appeal, the PTO acknowledged that that this particular finding might be in error after our construction of the term in NuVasive I. Intervenor’ s Br. at 47. And we find it to be in error because the Board’s construction is broader
t han that which we adopt in this opinion

. Second, the Board found that the record NuVasive produced contained insuffi cient evidence to demonstrate whether its XLIF surgical technique is, in fact, what the ’057 patent claims. Characterizing the evidence as “nebulous,” the PTO argues on appeal that the XLIF Surgical Technique Guide (Guide) NuVasive submitted uses the XLIF tradename at times in a manner that excludes limitations of the ’057 patent claims. For example, the Guide depicts dilators but does specify t hat these dilators are part of the XLIF instrument system ; rather, these dilators are part of the MaXcess ® II System . J.A. 2636. And the guide does not con sistently identify nerve

monitoring as a component of the XLIF system. J.A. 2638. Rather, the Neu roVision ® System appears to be a standalone nerve

- monitoring product that can be used with XLIF. Id . We disagree.

Aft er reviewing the Guide , we conclude that there is a nexus between the claimed invention and the XLIF surg ical technique . The Board and PTO suggest that only surgical tools and techniques labeled wit h the XLIF tradename are part of the XLIF surgical technique . But the Guide reveals otherwise. The Guide describes the “XLIF ® technique ” as utilizing “ a direct lateral, retroper itoneal approach to access the intervetebral disc without muscular disruption or trauma to nearby structures.” J.A. 2631. It does not describe any other surgical proc edures. And the Guide specifically identifies the MaXcess ® II Access System, MaXcess ® XLIF System, and Neur o-NUVASIVE , INC

. v. IANCU 19

V ision ® System as part of the require d instruments to successfully complete the technique. J.A. 2639 (“To successfully complete this technique, the following i nstruments are required: Radiolucent bendable surgical table, C

- Arm, Light source, MaXcess ® II Ac c ess System, MaXcess XLIF ® System, Triad ® General Instrument Tray, and NeuroVision ® JJB System.”)

. While the Guide does list the components of the “ XLIF Instrument System, ” it is very clear that the actual XLIF surgical technique requires more than just these instruments; it utilizes the MaXcess ® II Access, MaXcess ® XLIF, and Neu roV ision ® Systems in addition to general surgical tools such as nerve retractors, disc cutters, and curettes that are trad itionally employed in interbody fusion procedures

. J.A. 2633.

A t oral argument the PTO argued that the Board found insufficient nexus due to the “overlapping nature of the products in the field.” Oral Arg. at 29:13

– 29:18. The ’057 patent covers meth od cl aims whereas NuVasive’s XLIF -r elated products cover methods, devices, and sy stems. Id . at 29:18

– 29:31. While we agre e with this characterization, it does not speak to whether the scope of the claimed invention is reasonably commensurate with the XLIF surgical technique

. Due to the various devices and systems used in the XLIF procedure such as the MaXcess ® II Access, MaXcess ® XLIF, and Neuro V ision ® Systems, it is possible that the commercial success ev idence NuVasive presented did not come entirely from the XLIF surgical t echnique but rather also from the sales of these devices/systems for use in other surgical procedures. However, this does not mean that there is no nexus between the claimed invention and the XLIF surgical procedure.
Moreover, “[w] hen the patentee has presented undi sputed evidence that its product is the invention disclosed in the challenged claims, it is error for the Board to find to the contrary without further explanation.” PPC Broa d-NUVASIVE , INC

. v. IANCU 20

band , Inc. v. Corning Optical Communications RF , 815 F.3d 734, 747 (Fed. Cir. 2016). Here, w hile the Board did provide further explanation in finding the evidence NuVasive produced too nebulous to associate NuVasive’s objective evidence of nonobviousness with the XLIF surgical technique, we find this explanation unpersu asive. As explained above, we find that the Guide clearly lays out the devices and systems used in the XLIF surgical technique , some of which are not necessarily labeled with the XLIF trade name but are nonetheless utilized in the

sur gical technique

. On remand, the Board should re evaluate NuVasive’s objective evidence of nonobviousness such as long

- felt need, skepticism followed by praise and recognition, and commercial success under our finding that there is a nexus between the claimed invention and the XLIF surg ical technique . Our nexus finding, of course, does not mean that these secondary considerations require a finding of nonobviousness

. We simply require the Board to evaluate these secondary considerations when conside ring the obviousness inquiry as a whole . Further, we note that “evidence that widespread efforts by ordinarily skilled artisans had failed” is not necessarily required to show long

- felt need. Millennium Pharm. Inc. v. Sandoz, Inc. , 862 F.3d 1356, 1369 n. 5 (Fed. Cir. 2017) (“Althoug h ‘[e]vidence is particularly probative of obviousness when it demonstrates both that a demand existed for the patented invention, and that others tried but failed to satisfy that demand,’ a patent owner may establish a long

- felt need without presenting evidence of failure of others.”) (quoting In re Cyclobenzaprine Hydrochloride Extended

- Release Capsule Patent Litig. , 676 F.3d 1063, 1082 (Fed. Cir. 2012)). And we also note that the Board should not dismiss the testimony of paid experts. While the Board can and should weigh the credibility of any expert testimony, it should not outright disregard expert testimony from a witness simply because that individualNUVASIVE , INC

. v. IANCU 21

is compensated for his time and expense in testifying. Nothing in our opinion i n InTouch Techs., Inc. v. VGo Communications, Inc. , cited in the Board’s decision, stands for the proposition that paid expert testimony cannot be used to establish nonobviousness. 751 F.3d 1327, 1352 (Fed. Cir. 2014).

E Finally, we address the Board’s analysis of the scope of the prior art and motivation to combine Kossmann, Branch, Koros, and Kelleher to arrive at the claimed invention in the ’057 patent. NuVa sive makes two prim ary challenges to the Board’s obviousness analysis on appeal. First, NuVasive argues that the re is no motiv ation to combine the surgery of Kossmann with the surg ical tools of Branch and Koros. Second, NuVasive contends that there is no motivation to use the EMG

nerve

- monitoring technology taught in Kelleher during a lateral

, trans

- psoas surgical approach to the lumbar spine . We address each argument in turn.
As an initial matter, we note that the Board’s overly broad construction of the term “lateral, trans

- psoas path to the targeted lumbar spinal disc ” did not disturb its motivation to combine the prior art references analysis

. In NuVasive I, the primary dispute between the parties centered on the meaning of the word “lateral.” 693 F. App’x at 898. The specification of the patent in that case distinguished the “lateral” approach from the “postero

lateral” and “antero

- lateral” approaches. ’767 patent col. 7 ll. 43

– 51. And al l nine figures in the ’767 patent sho wing a path from the surgica l incision to the spine depict ed what amounts to a “ 3 o’clock or 9 o’clock approach to the spine

— essentially along a line 90° to a plane defined by the (roughly parallel) front -of- body midline and the spine ,” which is much mo re restrictive than the Board’s interpretation that covered any approach “lateral, to any degree, as compared to an anterior puncture.” 693 F.NUVASIVE , INC

. v. IANCU 22

App’x at 899 (citing the ’767 patent, Figs. 1, 9

– 10, 12

– 15, and 17

– 18). Accordingly, we concluded in NuVasive I that the broadest reasonable interpretation of “lateral” was an “approach to the lumbar spine that (1) approaches from the patient’s lateral aspect (or side); and (2) goes through the psoas muscle.” Id . at 900

– 901. Here, it is undisputed that Kossmann teaches a lateral approach to the spine. J.A. 12634 (Figure 1G), J.A. 12635. More over , when asked at oral argument, NuVasive’s attorney did not identify any part of the obviousness analysis other than objective evidence of nonobviousness analysis that relied

on the Board’s overly broad construction of “lateral, trans

psoas path to the targeted lumbar spinal disc .” Oral Arg

. at 5:50

– 6:55.

1. Kossmann, Branch, and Koros
With this in mind, we do not find that the B oard erred in concluding that a skilled artisan would be motiv at ed to combine the surgery described in Kossmann with the tools described in Branch and Koros. NuVasive argues on appeal that Kossmann does not teach a trans

- psoas surgical approach using retractors and dilators. Rather, NuVasive posits that Kossmann teaches retracting the psoas muscle in most patients and only uses blunt disse ction with a surgeon’s finger or a sponge on a sti ck to create a path through the psoas muscle in very athletic patients. A s a result, NuVasive argues that a skilled artisan would not have been motivated to modify the blunt dissection techniques in Kossmann with the dilation and retraction technique disclosed in Branch because b lunt dissection is safer for patient s

. During blunt disse ction, a surgeon carefully feels for nerves and can easily back off when near a nerve. Blunt dissection also sp lits the muscle along its fibers, thus ensuring that no muscle fibers are cut in the process of dissection. In NuVasive’s view, t his technique is not interchangeable with the dilator

- retractor approach taught in Branch because aNUVASIVE , INC

. v. IANCU 23

dilator is a hollow tube t hat cuts through fibers as it is pushed through muscle.

While NuVasive ’s argument is not meritless, the Board’s finding that a skilled artisan would have been motivated to combine Kossmann with Branch and Koros is supported by substantial evidence. D ila tors and retra ctors are ubiquitous surgical tools that skilled artisans knew how to use to penetrate tissue. J.A. 435

– 438. We are not persuad ed that these instruments are inherent ly less safe means for dissection than a surgeon’s f inger or a wet sponge o n a stick , particularly when the skilled artisan also simultaneously employs nerve

- monitoring technology. Instead, the Board’s finding to the contrary is reasonable in light of Dr. Lieber man’s testi mony that “[t]he use of instruments such as dilation and retraction assemblies is no more invasive than the use of blunt dissection, both techniques do the exact same t hing for the exact same purpose .” J.A. 435. Further , Branch itself teaches a tech nique that uses se quential dilators to slowly increase the size of a surgical site , and it teaches that this technique is broadly applicable in the field of spinal
surgery . This , the PTO argued, is precisely what a su rgeon’s finger or a sponge on a stick accomplishes.

NuVasive al so argues that the Board failed to demo nstrate why a skilled artisan would be motivated to modify Bra nch’s retractor to incorporate a fixation element as taught in Koros. According to NuVasive, Koros discloses a retractor with protruding screws that are s pecifically designed for an anterior surgical approach and cannot be used along a “lateral, trans

- psoas path” without significant redesign. See J.A. 4547. We do not find NuVasive’s argument persuasive. Our case law does not require that the Board explai n exactly how the fixation elements of Koros physically incorporate into Branch’s retractor. We agree with the Board that a skilled artisan would have
recog nized the stability and support the fixation element in Koros could add to the retractor assembly t aught inNUVASIVE , INC

. v. IANCU 24

Branch

. “[I]f a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill.” KSR , 550 U.S. at 417. NuVasive has not shown why adding a fixation element to Branch would be beyond the abilities of a skilled artisan. NuVasive’s expert testimony regarding the inoperability of the combination of Branch and Koros i s mere speculation and conclusory. Accordingly, the Board’s finding that a skilled artisan would have been motivated to combine Kossmann, Branch, and Koros is supported by substantial evidence.

2. Kossmann and Kelleher
Next, as to whether a skilled artisan would be mot ivated to use the EMG nerve

- monitoring technology taught in Kelleher during a lateral trans

- psoas surgery, we remand this issue to the Board for the parties to address whether Kelleher could be used to monitor the presence of the iliohypogastri c and ilioinguinal nerves. We emph asize that the scope of this remand on motivation to co mbine references is for the parties to address this narrow question. NuVasive asserts on appeal that a skilled artisan would not use the EMG nerve

- monitoring taught in Kelleher in the Kossmann procedure be cause : (1) Kossmann teaches an approach to the lumbar spine through the anteri or- most fibers of the psoas, which is a

“ safe zone ” where the important structures of the lumbar plexus do not typically reside

, and for which visual dete ction of nerve s is adequate ; and (2) Kelleher does not teach that its nerve

- monitoring technology can be used for detecting the iliohypogastric and ilioinguinal nerves Kossmann teaches to avoid.
We disagree with NuVasive that a skilled artisan would not be motivated to use neuro monitoring in the Kossmann procedure. B oth Kossmann and Branch teachNUVASIVE , INC

. v. IANCU 25

the desirability of avoiding nerves for patient safety

. Moreover, the ’057 patent does not require that the trans

psoas approach go through a specific part of the psoas, such as the lumbar plexus. Simply because surgeons could perform the procedure described in Kossmann with visual detection alone does not mean that a skilled art isan would not be motivated to use neuromonitoring to further ensu re patient safety

. However, we conclude that the Board’s position that a skilled artisan would be motivated to use Kelleher’s

nerve

- monitoring technique to detect the presence of the iliohypogastric and ilioinguinal nerves should be reman ded for further development

. The Board’s original r ationale was that nerve

- monitoring in general would be beneficial in spinal surgeries due to the need to avoid

nerves, and thus a skilled artisan would be motivated to use Kelleher’s nerve

- monitoring technique in Kossmann, even if Kossmann does not traverse the lumbar plexus. J.A. 962

– 63. In its Request to Reopen Prosecution

, NuVasive argue d that Kossmann does not mention an y danger of encountering nerves when splitting the psoas muscle. J.A. 1064. T he two nerves Kossmann mentions

, the iliohypogastric and ilioinguinal nerves, do not reside within the psoas muscle but rather are nerves that lie in the vicinity of the abdomen

. Id

. In resp onse to this, the Board acknowledged in its second decision that the il iohypogastric and ilioinguinal n erves are not located in the
pso as muscle, but noted that they are both still part of the lumbar plexus, which is what the trans

- psoas app roach taught in the ’057 patent seeks to avoid. J.A. 12 n. 4. Thus, the Board found it “of no moment that the nerves sought to be avoided in Kossmann are the iliohypogastric and ilioinguinal nerves [;] these are still nerves that Kossmann teaches should b e avoided in a lateral a pproach, which includes the approach taught by Kossmann that involves splitting the psoas muscle.” J.A. 12. The Board’s second decision thus appears to rest on a specificNUVASIVE , INC

. v. IANCU 26

theory: that a skilled artisan would be motivated to use K elleher’s nerve

- monitoring technology to detect the presence of the iliohypogastric and ilioingui nal nerves

. On appeal to us, NuV asive argues that Kelleher’s EMG nerve

- monitoring method is ineffective for monito ri ng these two nerves because these nerves do not supply motor neurons to the leg s . The iliohypogastric and il ioinguinal nerves supply sensory neurons to the leg and

p ubic region and motor neurons to the internal and tran sverse abdominal muscles. J.A. 2503

– 2504. EMG, the

nerve

- monitoring techniq ue taught in Kelleher, relies on the detection of motor neurons, not sensory neu rons, and Kelleher teaches that the relevant muscles for nerve detection in lumbar spinal surgery are those in a patient’s legs. J.A. 10200, 10215. Thus, according to NuVasiv e, Kelleher does not teach that the iliohypogast ric and ilioinguinal nerves are among those that may be detect ed with EMG nerve

- monitoring technology . The PTO does not directly res pond to this argument. It generally a ssert s that nerves in the psoas muscle are no different from other nerves in the body and that surgeons would have viewed existing nerve

- monitoring technology as appropriate for a lateral, trans

- psoas approach.

While we understand the PTO ’s position that the Bo ard was only responding to NuVasive’s arguments regarding the iliohypogastric and ilioinguinal nerves in its second decision

, t he question of whether Kelleher’s nerve

monitoring technique is applicable to the iliohypogastric and ilioinguinal nerves is a ne w finding that NuVasive has not had an adequate opportunity to address in the midst of this ever

- evolving proceeding . Accordingly, we remand this very narrow issue to the Board. We also note that there is nothing in our opinion precluding the Board from returning to its original position

— a finding that we do not review in this appeal

— that a skilled artisan would have been motivated to use Kelleher’s nerve

- monitoring technique in Kossmann’s lateral, trans

- psoas procedureNUVASIVE , INC

. v. IANCU 27

because Kossmann generally teaches that it is desirable to avoid nerves during surgical procedures.

C ONCLUSION We have considered NuVasive’s remaining arguments and find them unpersuasive. We modify the Board’s claim construction of “lateral, trans

- psoas path to the targeted lumbar spin al disc ” and construe the term in accordance with our opinion in NuVasive I . We reverse the Board’s finding of a lack of nexus between the method claimed in the ’057 patent and Nu Vasive’s XLIF surgical technique and remand for the Board to conduct a new

a nalysis of secondary considerat ions consistent with our nexus finding . And we affirm the Board’s remaining obviousness analysis except for its finding that a skilled artisan would have been motivated to use the nerve

monitoring technique taught in Kellehe r to detect the iliohypogastric and ilioinguinal nerves. We remand this narrow issue pertaining to the motivation to combine Kossmann, Branch, and Koros with Kelleher to the Board for further consideration

.

AFFIRM ED

- IN

- PART , REVERSED

- IN

- PART, AND REMANDED

C OSTS

No costs.