United States Court of Appeals 

for the Federal Circuit 

__________________________ 

IN RE HUAI-HUNG KAO, ANAND R. BAICHWAL, 

TROY MCCALL, AND DAVID LEE 

__________________________ 

2010-1307 

__________________________ 

Appeal from the United States Patent and Trademark 

Office, Board of Patent Appeals and Interferences in 

application Serial No. 11/680,432. 

__________________________ 

IN RE HUAI-HUNG KAO, ANAND R. BAICHWAL, 

TROY MCCALL, AND DAVID LEE 

__________________________ 

2010-1308 

__________________________ 

Appeal from the United States Patent and Trademark 

Office, Board of Patent Appeals and Interferences in 

application Serial No. 12/167,859. 

__________________________ 

IN RE HARRY AHDIEH 

__________________________ 

2010-1309 

__________________________ 
2 IN RE KAO, IN RE KAO, IN RE AHDIEH

Appeal from the United States Patent and Trademark 

Office, Board of Patent Appeals and Interferences in 

application Serial No. 11/766,740. 

__________________________ 

Decided: May 13, 2011 

__________________________ 

JEFFREY I. D. LEWIS, Patterson, Belknap Webb & Tyler, LLP, of New York, New York, argued for appellants. 

With him on the briefs were MELISSA MANDRGOC, and 

CATHERINE A. WILLIAMS; and GUY DONATIELLO, Endo 

Pharmaceuticals, Inc., of Chadds Ford, Pennsylvania; and 

JOSEPH MAHONEY, Mayer Brown LLP, of Chicago, Illinois. 

FRANCES M. LYNCH, Associate Solicitor, Office of the 

Solicitors, United States Patent and Trademark Office, of 

Alexandria, Virginia, argued for appellee in both 2010-

1307 and 2010-1308. BENJAMIN D.M. WOOD, Associate 

Solicitor, argued for appellee in 2010-1309. With them on 

the briefs was RAYMOND T. CHEN, Solicitor. 

__________________________ 

Before RADER, Chief Judge, LINN and MOORE, Circuit 

Judges.

LINN, Circuit Judge. 

Endo Pharmaceuticals, Inc. (“Endo”) is the assignee of 

three patent applications related to controlled-release 

tablets containing the opioid narcotic oxymorphone. The 

Board of Patent Appeals and Interferences (“the Board”), 

in separate appeals, affirmed the rejection of the claims of 

each application as obvious, and Endo has separately 

appealed each decision to this court. 

The Board affirmed the rejection of all pending claims 

of United States Patent Application No. 11/680,432 (“the 

’432 Application”), United States Patent Application No. 
IN RE KAO, IN RE KAO, IN RE AHDIEH 3

12/167,859 (“the ’859 Application”), and United States 

Patent Application No. 11/766,740 (“the ’740 Application”) 

principally over a prior art international patent application that is involved in each appeal. Endo timely appealed each decision of the Board, and this court has 

jurisdiction under 28 U.S.C. § 1295(a)(4)(A). 

Because the Board based its conclusion of obviousness 

regarding the ’432 Application on factual findings lacking 

in substantial evidence, this court vacates and remands. 

Because the Board’s conclusions regarding the obviousness of the ’859 and ’740 Applications were supported by 

substantial evidence, this court affirms the Board’s decisions regarding those two applications. 

BACKGROUND

I. The ’432 Application 

The claimed invention of the ’432 Application relates 

to drug formulations containing opioids, a type of narcotic 

frequently used to manage chronic pain. To provide 

consistent pain relief, a minimum level of the opioid must 

be maintained in the blood. Opioids, however, are typically available in immediate release formulations that 

quickly release the entire dose of the opioid into the body. 

Moreover, some opioids are rapidly metabolized by the 

liver (a phenomenon known as the “first-pass effect”) 

resulting in the drug having a low “bioavailability.” When 

a drug has low bioavailability this means that only a 

small amount of the drug is systemically available 

throughout the body. Because of these drawbacks, immediate release opioid formulations must be administered 

frequently (e.g., every 4-6 hours) to maintain continuous 

pain relief. But frequent administration of opioids can 

result in a variety of side effects, ranging from disturbed 

sleep to altered mental states. 
4 IN RE KAO, IN RE KAO, IN RE AHDIEH

To overcome the difficulties associated with immediate release formulations, the ’432 Application discloses 

controlled release formulations containing the opioid 

oxymorphone, and capable of relieving pain for between 

twelve and twenty-four hours. 

Independent claims 1 and 20, as well as dependent 

claims 2-3 and 5-19, are pending in the ’432 Application. 

Because the ’432 Application was filed under the Accelerated Examination Program of the United States Patent 

and Trademark Office (“the Office”), Endo was limited to 

arguing the patentability of independent claims 1 and 20. 

Claim 1 reads as follows (relevant terms emphasized): 

1. An analgesically effective controlled release 

pharmaceutical composition with a twelve hour 

dosing interval in the form of a tablet, comprising 

oxymorphone or a pharmaceutically acceptable 

salt thereof as the sole active ingredient in the 

tablet and a controlled release delivery system 

comprising at least one pharmaceutical excipient, 

wherein upon placement of the composition in an 

in vitro dissolution test comprising USP Paddle 

Method at 50 rpm in 500 ml media having a pH of 

1.2 to 6.8 at 37o C, about 15% to about 50%, by 

weight, of the oxymorphone or salt thereof is released from the tablet at about 1 hour in the test. 

Claim 20 is similar to claim 1 but recites that “about 

45% to about 80%, by weight, of the oxymorphone or salt 

thereof is released from the composition at about four 

hours in the test, and at least about 80%, by weight, of the 

oxymorphone or salt thereof is released from the composition at about 10 hours in the test.” 

The examiner rejected claims 1 and 20 as obvious in 

view of Patent Cooperation Treaty Publication No. WO 

01/08661 to Maloney (“Maloney”), both alone and in 
IN RE KAO, IN RE KAO, IN RE AHDIEH 5

combination with United States Patent No. 5,047,248 to 

Calanchi et al. As is relevant here, the examiner found 

that, with the exception of the claimed dissolution rate, 

Maloney disclosed controlled release opioid formulations 

that taught the recited limitations. The examiner stated 

that the burden fell on Endo to show why Maloney failed 

to satisfy the claimed dissolution rate because, in her 

view, the controlled release system described by Maloney 

satisfied the other limitations of the claims. 

In response, Endo submitted declarations explaining 

that because Maloney only disclosed a dissolution profile 

for a controlled release formulation containing oxycodone, 

an opioid with markedly different bioavailability than 

oxymorphone, it provided little guidance on the appropriate design of a controlled release oxymorphone formulation. The declarations further explained that controlled 

release oxymorphone formulations exhibit an unexpected 

result: Over time the formulations cause multiple peaks 

in oxymorphone blood concentration, which help prevent 

patients from building a tolerance to the opioid. Endo 

also included evidence that Opana® ER, a commercial 

embodiment of the invention, had experienced significant 

commercial success. The examiner concluded that the 

declarations were insufficient to show that Maloney did 

not suggest the claimed range of dissolution profiles. The 

examiner also found that the evidence of unexpected 

results and commercial success offered by Endo was not 

commensurate with the scope of the claims, because that 

evidence largely related to Opana® ER and the claims 

encompassed a large number of other formulations, for 

which no secondary considerations were shown. 

On appeal, the Board affirmed the examiner’s rejection, relying exclusively on Maloney and in particular on 

the controlled release formulation denominated “Formula 

6.” The Board recognized that Maloney disclosed that 

Formula 6 contains oxycodone instead of oxymorphone as 
6 IN RE KAO, IN RE KAO, IN RE AHDIEH

recited in the claims. The Board also recognized that 

Maloney disclosed dissolution data for Formula 6 measured by the USP Basket Method, not the claimed USP 

Paddle Method. Nevertheless, the Board concluded that 

Formula 6 rendered the claims obvious. The Board 

determined that it would have been obvious to one of skill 

in the art to replace the oxycodone in Formula 6 with 

oxymorphone because Maloney generally identifies oxymorphone as a preferred opioid for use in his invention. 

Regarding the claimed dissolution rate, the Board found 

that a declaration submitted by Endo in response to the 

first office action suggested that the dissolution rate as 

measured by the Basket Method was 1.3 times faster than 

the rate as measured by the Paddle Method. Applying 

this correlation to the dissolution data for the Formula 6 

oxycodone disclosed in Maloney, the Board found that 

Formula 6 satisfied the claimed dissolution profile. The 

Board then appeared to reason that if one were to substitute oxymorphone for oxycodone in Maloney’s Formula 6, 

the result would be an oxymorphone controlled release 

pill with a dissolution profile within the range of pending 

claim 1. 

The Board then turned to the evidence of secondary 

considerations. It assumed that the evidence of commercial success and unexpected results presented by Endo 

was sufficient to overcome a prima facie case of obviousness with respect to the commercial embodiment but, like 

the examiner, concluded that the evidence was not commensurate with the scope of the claims and, therefore, 

failed to overcome the rejections. 

II. The ’859 Application 

The ’859 Application discloses a method of relieving 

pain using oxymorphone in a controlled release delivery 
IN RE KAO, IN RE KAO, IN RE AHDIEH 7

system to overcome the difficulties associated with immediate release formulations of opioids. 

Claims 8-27 are pending and on appeal. Because the 

’859 Application was filed under the Accelerated Examination Program, Endo was limited to arguing the patentability of the independent claims and only argued 

independent claims 8 and 21 before the Board. Thus, the 

claims of the ’859 Application stand or fall with independent claims 8 and 21. 

Claim 8 of the ’859 Application is directed to a method 

for treating pain by administering oxymorphone in a 

controlled release formulation that (1) provides at least 12 

hours of sustained pain relief and (2) results in a “Cmax” 

(maximum concentration) at least about 50% higher when 

administered to fed versus fasting patients. Claim 8 

reads as follows (relevant terms emphasized): 

8. A method for treating pain in a human subject 

in need of acute or chronic pain relief, comprising 

the steps of: 

(a) Providing a solid oral dosage form comprising 

about 5 mg to about 80 mg oxymorphone or a 

pharmaceutically acceptable salt thereof in a controlled release delivery system with a release rate 

profile designed to provide an adequate blood 

plasma level over at least 12 hours to provide sustained pain relief over this same period, the system comprising a filler and a hydrophilic material, 

wherein oxymorphone is the sole active ingredient; and, 

(b) administering the dosage form to the subject, 

wherein the oxymorphone Cmax is at least about 

50% higher when the dosage form is administered 

to the subject under fed versus fasted conditions.
8 IN RE KAO, IN RE KAO, IN RE AHDIEH

Claim 21 additionally requires, among other limitations, that the controlled release formulation include a 

hydrophobic material. Claim 21 reads as follows (relevant 

terms emphasized): 

21. A method for treating pain in a human subject in need of acute or chronic pain relief, comprising the steps of 

(a) Providing a solid oral dosage form comprising 

about 5 mg to about 80 mg oxymorphone or a 

pharmaceutically acceptable salt thereof in a controlled release delivery system with a release rate 

profile designed to provide an adequate blood 

plasma level over at least 12 hours to provide sustained pain relief over this same period, the system comprising: 

(i) a hydrophilic material 

(ii) a hydrophobic material

(iii) a cationic cross-linking agent, and 

(iv) a filler, 

wherein oxymorphone is the sole active ingredient; and 

(b) administering the dosage form to the subject, 

wherein the oxymorphone Cmax is at least about 

50% higher when the dosage form is administered 

to the subject under fed versus fasted conditions. 

The examiner rejected claims 8 and 21 as obvious in 

view of, among other references, Maloney. The examiner 

found that Maloney “teaches oral sustained release 

preparations of opioid analgesics” with the use of oxymorphone as a preferred opioid. 
IN RE KAO, IN RE KAO, IN RE AHDIEH 9

On appeal, the Board affirmed the examiner’s rejection, relying exclusively on Maloney. The Board found 

that Maloney discloses a controlled release formulation 

with an opioid in amounts of 5-100 mg and that oxymorphone is a preferred opioid. The Board found that Maloney further teaches using calcium sulfate (a cross 

linking agent), lactose (a filler), and hydrogenated vegetable oil (a hydrophobic material) in his formulation. Based 

on these disclosures, the Board determined that it would 

have been obvious to a person of ordinary skill in the art 

to formulate the claimed oral dosage form and to administer the form to the subject as claimed in the ’859 Application. 

The Board then turned to the evidence of secondary 

considerations. Just as it did with the ’432 Application, it 

assumed that the evidence of commercial success and 

unexpected results presented by Endo was sufficient to 

overcome a prima facie case of obviousness with respect to 

the commercial embodiment but agreed with the examiner that the evidence was not commensurate with the 

scope of the claims and, therefore, failed to overcome the 

rejections. 

III. The ’740 Application 

The ’740 Application was likewise filed under the Accelerated Examination Program; so only the independent 

claims 21, 25, and 30 are potentially at issue. For reasons 

that will become clear below, we limit our discussion to 

claim 21. 

Independent claim 21 reads: 

21. A method of providing extended pain relief to 

patients in need thereof, comprising: 
10 IN RE KAO, IN RE KAO, IN RE AHDIEH

providing information that the average bioavailability of oxymorphone in an oral extended release 

formulation designed to have a 12 hour dosing cycle is increased by at least about 26% for subjects 

with renal impairment compared to that for 

healthy subjects, and 

providing a therapeutically effective amount of 

such an extended release oral dosage form of oxymorphone or its pharmaceutically acceptable salt 

thereof. 

’740 Application. 

The Office rejected claim 21 as obvious over three different combinations. We need focus on only one: Maloney 

in view of United States Patent Publication No. 

2002/0032581 (“Reitberg”). The examiner found that 

“Maloney teaches a controlled-release dosage form comprising oxymorphone,” that Reitberg teaches a clinical 

evaluation kit for measuring the effectiveness of treatment of a specific individual comprising a medication and 

instructions, and that it would have been obvious to 

combine the two. Ahdieh argued to the Board that it 

would not have been obvious to a person of ordinary skill 

to combine the two references because the correlation 

between renal impairment and bioavailability of controlled release oxymorphone was not previously known, 

and because, in any case, evidence of commercial success 

and unexpected results compel a determination of nonobviousness. 

DISCUSSION

A claimed invention is unpatentable “if the differences 

between the subject matter sought to be patented and the 

prior art are such that the subject matter as a whole 

would have been obvious at the time the invention was 
IN RE KAO, IN RE KAO, IN RE AHDIEH 11

made to a person having ordinary skill in the art.” 35 

U.S.C. § 103(a). Whether an invention is obvious is a 

question of law based on underlying facts. In re Kotzab, 

217 F.3d 1365, 1369 (Fed. Cir. 2000). This court reviews 

the Board’s ultimate determination of obviousness de 

novo and the Board’s fact findings for substantial evidence. In re Gartside, 203 F.3d 1305, 1316 (Fed. Cir. 

2000). “Substantial evidence is such relevant evidence as 

a reasonable mind might accept as adequate to support a 

conclusion.” In re Kumar, 418 F.3d 1361, 1366-67 (Fed. 

Cir. 2005) (quotation omitted). 

I. The ’432 Application 

A. Obviousness 

Endo contends that the examiner failed to present a 

prima facie case of obviousness because there is no evidence that substituting oxymorphone for oxycodone in 

Maloney’s Formula 6 would result in a formulation that 

satisfies the claimed dissolution profile. Endo claims that 

the Board improperly relied on speculation and hindsight 

to conclude otherwise. 

The Office argues that the Board correctly concluded 

that replacing oxycodone with oxymorphone in Formula 6 

would result in the claimed invention. The Office asserts 

that Maloney provides ample reason for one of skill in the 

art to alter Formula 6 as suggested by the Board and 

teaches that Formula 6 can relieve pain for twelve hours. 

It claims that the Board reasonably concluded that there 

is a correlation between the claimed dissolution test (the 

USP Paddle Method) and the test disclosed by Maloney 

(the USP Basket Method), and applying this correlation 

demonstrates that Formula 6 has the claimed dissolution 

profile. 
12 IN RE KAO, IN RE KAO, IN RE AHDIEH

Before turning to the merits of Endo’s appeal, we first 

consider the Office’s contention that only claim 1, and not 

claim 20, is properly before us on appeal. The Office 

contends that Endo did not present separate arguments 

concerning claim 20 to the Board, and that claim 20 

therefore stands or falls with claim 1. Endo responds by 

pointing to various portions of the record where it contends it separately argued the patentability of claim 20. 

 We agree with the Office that Endo waived the right 

to have the Board separately consider claim 20. Under 37 

C.F.R. § 41.37(c)(1)(vii), “the failure of appellant to separately argue claims which appellant has grouped together 

shall constitute a waiver of any argument that the Board 

must consider the patentability of any grouped claim 

separately.” The portions of the record cited by Endo 

merely mention claim 20 and lack any type of separate, 

substantive argument concerning the claim as required by 

37 C.F.R. § 41.37(c)(1)(vii). See also In re McDaniel, 293 

F.3d 1379, 1383 (Fed. Cir. 2002) (“[T]he Board is free to 

select a single claim from each group of claims subject to a 

common ground of rejection as representative of all claims 

in that group and to decide the appeal of that rejection 

based solely on the selected representative claim” in the 

absence of a clear statement asserting separate patentability of the claims.). 

On the merits, this court agrees with Endo that the 

Board relied on erroneous reasoning in making the factual determinations that underlie its conclusion that 

claim 1 is obvious, and that its factual findings are therefore unsupported by substantial evidence. However, 

because the evidence of record may yet satisfy the required substantial evidence standard, the Board’s determination will be vacated and remanded. 

An examiner bears the initial burden of presenting a 

prima facie case of obviousness. See In re Glaug, 283 F.3d 
IN RE KAO, IN RE KAO, IN RE AHDIEH 13

1335, 1338 (Fed. Cir. 2002). Once the examiner establishes a prima facie case of obviousness, the burden shifts 

to the applicant to rebut that case. “The prima facie case 

is a procedural tool, and requires that the examiner 

initially produce evidence sufficient to support a ruling of 

obviousness; thereafter the burden shifts to the applicant 

to come forward with evidence or argument in rebuttal.” 

In re Kumar, 418 F.3d at 1366. However, once the applicant has come forward with rebuttal evidence, the examiner must consider the totality of the evidence to 

determine whether the obviousness rejection should 

stand. “When rebuttal evidence is provided, the prima 

facie case dissolves, and the decision is made on the 

entirety of the evidence.” Id. 

The Board first observed that Maloney discloses specific controlled release formulations of oxycodone, that 

Maloney states that oxymorphone can also be used in a 

controlled release formulation, and that it is indeed a 

preferred compound. Based on these observations, the 

Board concluded that it would have been obvious to 

substitute oxymorphone in Maloney’s Formula 6 (that 

being one of the controlled release oxycodone formulations 

disclosed in Maloney). The Board then observed that 

while Maloney does not disclose the dissolution rate of 

Formula 6 as measured by the Paddle Method, it does 

disclose that rate as measured by the Basket Method. To 

support that observation, the Board relied upon the 

Second Chang declaration to find a correlation between 

Paddle Method and Basket Method measurements for 

Opana® ER after one hour of dissolution. Applying that 

correlation to the Basket Method measurements of the 

oxycodone Formula 6 disclosed in Maloney, the Board 

concluded that oxycodone Formula 6 fell within the dissolution rate range of claim 1. On the basis of these factual 

determinations, the Board concluded that “the product 

made obvious by Maloney [i.e. Formula 6 with an oxymorphone substitute] would have a dissolution rate 
14 IN RE KAO, IN RE KAO, IN RE AHDIEH

between 15% and 50% after one hour when measured by 

the USP Paddle Method.” 

Accepting that it would be obvious to substitute oxymorphone in Maloney’s Formula 6, the Board’s reasoning 

nonetheless does not pass the substantial evidence 

threshold as to whether such a substitution would indeed 

fall within the dissolution profile of pending claim 1. As 

an initial matter, it should be clear that it makes no 

difference, a priori, to the question of obviousness whether 

the hypothetical person of ordinary skill in the art would 

have understood the claimed dissolution profile in terms 

of a Paddle-Method or a Basket-Method test range, just as 

it would make no difference whether the hypothetical 

person of skill in the art preferred to think in English or 

Metric units. The claimed subject matter is not presumed 

to change as a function of how one elects to measure it. 

The reason this “correlation” appears to matter on the 

Board’s formulation of the present case is that there is a 

lack of direct factual support in the record for the view 

that the claimed range of dissolution rates actually overlaps with the dissolution rate disclosed in Maloney, a 

premise upon which the Board’s reasoning is founded. 

Thus, while it matters not whether the hypothetical 

skilled artisan would have appreciated the “correlation” at 

issue here, it matters greatly whether anything the 

skilled artisan would be prompted by the prior art to do is 

in fact within the scope of the pending claim. 

The declaration relied upon by the Board does not 

provide substantial evidence for its finding of a correlation between the Basket and Paddle Methods. The Board 

relied on four data points from an exhibit correlating the 

dissolution rates of Opana® ER, when tested by both 

methods, and Maloney’s Formula 6, tested only by the 

Basket Method, and concluded, without any reasoning, 

that because the Basket Method dissolution in the first 

hour for Opana® ER was 1.3 times faster than the disso-
IN RE KAO, IN RE KAO, IN RE AHDIEH 15

lution rate of the Paddle Method for Opana® ER, this 

correlation would also hold for Maloney’s Formula 6. 

Moreover, the declarant responsible for the exhibit expressly stated that there is no general correlation between 

the Basket and Paddle Methods and cited prior art literature that supported this conclusion. The Board has not 

provided any reason, apart from its own statement to the 

contrary, to question this conclusion. The Board’s own 

conjecture does not supply the requisite substantial 

evidence to support the rejections, i.e., “such evidence as a 

reasonable mind might accept as adequate to support a 

conclusion.” Consol. Edison Co. v. Nat’l Labor Relations 

Bd., 305 U.S. 197, 229 (1938). For these reasons, the 

Board’s reliance on its own conjecture regarding whether 

a direct substitution of oxymorphone in Formula 6 would 

satisfy the claimed range of dissolution rates is improper. 

While the Board did not base its factual conclusions 

regarding the correlation of the two ranges on substantial 

evidence, the importance, or lack thereof, of the claimed 

range to the alleged nonobviousness of the invention is a 

question we leave for the Board to consider on remand. 

See, e.g., Ormco Corp. v. Align Technology, Inc., 463 F.3d 

1299, 1311 (Fed. Cir. 2006) (explaining that overlap 

between claimed range and prior art gives rise to a presumption of obviousness; where claimed range and prior 

art value are insubstantially different, prima facie obviousness rejection is proper). 

The Board’s decision is vacated and remanded so that 

the Board can consider whether, under the proper analysis, the evidence of record is sufficient to maintain an 

obviousness rejection. As the Supreme Court has explained: 

When there is. . . market pressure to solve a problem and there are a finite number of identified, 

predictable solutions, a person of ordinary skill in 
16 IN RE KAO, IN RE KAO, IN RE AHDIEH

the art has good reason to pursue the known options within his or her technical grasp. If this 

leads to the anticipated success, it is likely the 

product not of innovation but of ordinary skill and 

common sense. 

KSR Intern. Co. v. Teleflex Inc., 550 U.S. 398, 402-403 

(2007). Thus, while the Board should neither rely upon 

conclusory reasoning nor its own conjecture in assessing 

the weight of evidence, the Board may, or may not, still 

find that the evidence supports the examiner’s rejection. 

B. Secondary Considerations 

Endo argues that it submitted evidence of unexpected 

results and commercial success sufficient to rebut a prima 

facie showing of obviousness. The Office contends that 

the Board correctly discounted the secondary considerations evidence submitted by Endo because the evidence 

was not commensurate with the scope of the claims. Endo 

is correct that the Board erred by failing to give the 

evidence of secondary considerations its due weight. But 

there were nonetheless other defects in at least the presentation of this evidence. 

To start, when secondary considerations are present, 

though they are not always dispositive, it is error not to 

consider them. See Stratoflex v. Aeroquip Corp., 713 F.2d 

1530, 1538 (Fed. Cir. 1983) (“[E]vidence rising out of the 

so-called ‘secondary considerations’ must always when 

present be considered en route to a determination of 

obviousness.”); Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 

1372 (Fed. Cir. 2007) (“Although secondary considerations 

must be taken into account, they do not necessarily control the obviousness conclusion.”). 

Evidence of secondary considerations must be reasonably commensurate with the scope of the claims. See
IN RE KAO, IN RE KAO, IN RE AHDIEH 17

In re Tiffin, 448 F.2d 791, 792 (CCPA 1971); In re Hiniker, 

150 F.3d 1362, 1369 (Fed. Cir. 1998). This does not mean 

that an applicant is required to test every embodiment 

within the scope of his or her claims. If an applicant 

demonstrates that an embodiment has an unexpected 

result and provides an adequate basis to support the 

conclusion that other embodiments falling within the 

claim will behave in the same manner, this will generally 

establish that the evidence is commensurate with scope of 

the claims. See In re Greenfield, 571 F.2d 1185, 1189 

(CCPA 1978) (concluding that evidence of secondary 

considerations was not commensurate with the scope of 

the claims where that evidence related to a single compound and there was no adequate basis to conclude that 

other compounds included within the scope of the claims 

would exhibit the same behavior); In re Cescon, 474 F.2d 

1331, 1334 (CCPA 1973) (concluding that, although not 

every compound within the scope of the claims was tested, 

the evidence of secondary considerations was sufficient 

where evidence showed a correlation and there was no 

factual basis to expect the compounds to behave differently in different environments). 

But there is a more fundamental requirement that 

must be met before secondary considerations can carry 

the day. “For objective evidence of secondary considerations to be accorded substantial weight, its proponent 

must establish a nexus between the evidence and the 

merits of the claimed invention.” Wyers v. Master Lock 

Co., 616 F.3d 1231, 1246 (Fed. Cir. 2010) (quotation 

omitted). Where the offered secondary consideration 

actually results from something other than what is both 

claimed and novel in the claim, there is no nexus to the 

merits of the claimed invention. Tokai Corp. v. Easton 

Enters., Inc., 632 F.3d 1358, 1369 (Fed. Cir. 2011) (“If 

commercial success is due to an element in the prior art, 

no nexus exists.”); Ormco Corp., 463 F.3d at 1312 (“[I]f the 

feature that creates the commercial success was known in 
18 IN RE KAO, IN RE KAO, IN RE AHDIEH

the prior art, the success is not pertinent.”); In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990) (“The law is 

replete with cases in which the difference between the 

claimed invention and the prior art is some range or other 

variable within the claims . . . . [and] in such a situation, 

the applicant must show that the particular range is 

critical, generally by showing that the claimed range 

achieves unexpected results relative to the prior art 

range.” (citations omitted)). 

1. Unexpected Results 

The Board acknowledged applicant’s evidence that, 

unlike immediate release formulations, ingesting a particular disclosed controlled-release formulation resulted in 

unexpected multiple peaks in oxymorphone blood concentration. Despite assuming that this evidence was sufficient to overcome the prima facie case of obviousness for 

that formulation, the Board disregarded this evidence 

because, in its view, the evidence was not commensurate 

with the scope of the claims. 

The Board noted that the ’432 Application disclosed 

that a particular controlled release formulation caused 

unexpected multiple peaks in oxymorphone blood concentration, while immediate release formulations did not. In 

light of this, the Board concluded that this unexpected 

property must be caused by some component of that 

particular disclosed controlled-release formulation. This 

is unsupported by the record. The only evidence of record 

indicates that the unexpected in vivo characteristics of 

oxymorphone controlled release compositions did not 

result from properties unique to any specific commercial 

embodiment. Endo supplied a declaration from one of its 

experts stating that, after reviewing clinical studies and 

scientific literature, it appeared that extended release 

formulations of oxymorphone—not limited to formulations 
IN RE KAO, IN RE KAO, IN RE AHDIEH 19

with any specific excipient—cause multiple peaks in 

oxymorphone blood concentration. The Board did not 

challenge this conclusion. Because the Board ignored the 

evidence of record and relied instead upon its own conjecture, its treatment of Endo’s argument regarding unexpected results was improper. 

On remand, the Board, in considering the evidence of 

unexpected results, should determine whether there is a 

nexus between the unexpected in vivo concentration 

profile and aspects of the claimed invention not already 

present in the prior art. More specifically, for the unexpected in vivo concentration profile of the applicant’s 

product to have substantial weight, there must be a nexus 

to some aspect of the claim not already in the prior art, 

such as the claimed range of dissolution rates, as against 

other unclaimed prior-art dissolution rates. 

2. Commercial Success 

The Board also discounted Endo’s evidence of commercial success of Opana® ER on the grounds that it was 

not commensurate with the scope of the claims. But an 

applicant “need not sell every conceivable embodiment of 

the claims in order to rely upon evidence of commercial 

success, so long as what was sold was within the scope of 

the claims.” In re DBC, 545 F.3d 1373, 1384 (Fed. Cir. 

2008). See also Applied Materials, Inc. v. Advanced 

Semiconductor Materials Am. Inc., 98 F.3d 1563, 1570 

(Fed. Cir. 1996) (“[A] patentee need not show that all 

possible embodiments within the claims were successfully 

commercialized in order to rely on the success in the 

marketplace of the embodiment that was commercialized.”). As this court recently explained, “[i]t seems 

unlikely that a company would sell a product containing 

multiple, redundant embodiments of the patented invention . . . . Under the [Office’s] logic, there would never be 
20 IN RE KAO, IN RE KAO, IN RE AHDIEH

commercial success evidence for a claim that covers more 

than one embodiment.” In re Glatt Air Techniques, Inc., 

630 F.3d. 1026, 1030 (Fed. Cir 2011). The Board’s refusal 

to credit the applicant’s evidence of commercial success 

because it was not proven across the entire claimed range 

of dissolution rates was improper. 

Nonetheless, the record is nearly silent on whether 

the commercial success was caused by the merits of the 

invention as distinct from the prior art. In short, if it is 

not established that the claimed and novel range for a 

controlled release oxymorphone formulation causes commercial success where the prior art range would not, then 

it will be difficult to show the required nexus. Applicants’ 

expert opined that the unexpected in vivo concentration 

was likely responsible for the commercial success of the 

embodying product. Applicants’ expert further opined 

that the amelioration of analgesic tolerance to which 

Applicants attribute commercial success “is precisely the 

practical impact [he] would expect from the biphasic and 

triphasic pK behavior” of the commercial embodiment. 

But if the same behavior would be observed in any oxymorphone controlled release formulation, then there is no 

necessary nexus between the commercial success and the

claimed formulation. On remand, the Board, in considering the commercial success argument, should make a 

factual determination as to whether the commercial 

success of the embodying product resulted from the merits 

of the claimed invention as opposed to the prior art or 

other extrinsic factors. 

II. The ’859 Application 

A. Obviousness 

Endo advances three main arguments in challenging 

the Board’s finding of obviousness. First, Endo argues 
IN RE KAO, IN RE KAO, IN RE AHDIEH 21

that Maloney fails to disclose the claimed food effects. 

Second, Endo argues that Maloney fails to disclose the 12-

hour effectiveness of the claimed controlled release formulation of oxymorphone. Third, Endo argues that Maloney 

fails to disclose the claimed combination that includes a 

hydrophobic material. We address each argument in 

turn. 

1. Food Effects Limitation 

Endo argues that Maloney does not expressly disclose 

the “food effect” limitation: “wherein the oxymorphone 

Cmax is at least about 50% higher when the dosage form 

is administered to the subject under fed versus fasted 

conditions.” Endo asserts that the Board erroneously 

relied on the teaching in the specification of the ’859 

Application that the claimed “food effect” was a property 

of oxymorphone and that Maloney inherently disclosed 

the limitation. Endo argues that an obviousness rejection 

can only be based on what is known by those of skill in 

the art at the time of the invention, and there is no evidence in the record that anyone recognized the claimed 

food effect at that time. 

The Office responds that substantial evidence supports the Board’s finding of inherency. The Office further 

responds that the Board’s reliance upon the specification 

of the ’859 Application to support this conclusion is entirely proper. Further, the Office responds that inherency 

is indeed a part of the obviousness inquiry. 

This court agrees with the Office. Substantial evidence supports the Board’s finding, based upon the specification, which confirms that the claimed “food effect” is 

an inherent property of oxymorphone itself, present both 

in controlled release and immediate release formulations 

of that drug. See In re Kubin, 561 F.3d 1351, 1357 (Fed. 
22 IN RE KAO, IN RE KAO, IN RE AHDIEH

Cir. 2009) (stating “[e]ven if no prior art of record explicitly discusses the [limitation], [applicant’s] application 

itself instructs that [the limitation] is not an additional 

requirement imposed by the claims on the [claimed invention], but rather a property necessarily present in [the 

claimed invention]”); see also King Pharmaceuticals, Inc. 

v. Eon Labs, Inc., 616 F.3d 1267, 1275-76 (Fed. Cir. 2010) 

(stating that “merely discovering and claiming a new 

benefit of an old process cannot render the process again 

patentable” (citations omitted)). This is not a case where 

the Board relied on an unknown property of prior art for a 

teaching. Rather, Maloney’s express teachings render the 

claimed controlled release oxymorphone formulation 

obvious, and the claimed “food effect” adds nothing of 

patentable consequence. 

2. 12-Hour Effectiveness Limitation 

Endo argues that Maloney does not expressly disclose 

the recited 12-hour effectiveness limitation. Endo asserts 

that it provided evidence that one of skill in the art would 

not have expected that oxymorphone could be substituted 

for oxycodone because (1) oxymorphone has a much lower 

bioavailability than oxycodone and (2) oxymorphone is 

subject to the “first-pass effect.” 

The Office responds that the Board found that Maloney expressly teaches using oxymorphone in the disclosed formulations. Although Endo’s experts essentially 

stated their view that Maloney did not enable the disclosed oxymorphone formulation, their statements were 

based on various “concerns” that fall short of establishing 

that the Maloney reference was non-enabling. See In re 

Merck & Co., Inc., 800 F.2d 1091, 1097 (Fed. Cir. 1986) 

(concluding that obviousness does not require absolute 

predictability, only a reasonable expectation that the 

beneficial result will be achieved).
IN RE KAO, IN RE KAO, IN RE AHDIEH 23

This court agrees with the Office. Substantial evidence supports the Board’s finding. The Board found that 

Maloney teaches a controlled release opioid formulation 

comprising an opioid compound in amounts of 5-100 mg. 

Maloney further discloses that oxymorphone is a preferred opioid compound. Finally, Maloney discloses that 

its dosage form provides a dissolution rate of 60%-80% 

active agent released after 12 hours. Based on these 

findings, the Board reasonably concluded that Maloney’s 

active agent would still be effective after 12 hours because 

it is still being released from Maloney’s dosage form at 12 

hours. Notwithstanding the “concerns” expressed by 

Endo’s experts, Endo has failed to provide record evidence 

showing that Maloney’s disclosure fails to provide a 

reasonable expectation of obtaining the plasma levels of 

oxymorphone suggested by Maloney and required by 

claims 8 and 21. See Merck, 800 F.2d at 1097. Substantial evidence supports the Board’s conclusion that the 

oxymorphone formulation disclosed in Maloney would 

satisfy the claimed 12-hour effectiveness limitation. 

3. Hydrophobic Limitation 

Endo argues that Maloney fails to teach a controlled 

release formulation including both a hydrophilic and a 

hydrophobic material. According to Endo, although 

Maloney discloses an example using a hydrophobic lubricant, the example describes this hydrophobic material as 

“optional” and it is used as a lubricant, not as part of the 

release formulation. 

The Office responds that substantial evidence supports the Board’s finding that Maloney teaches the use of 

hydrophilic polymers with lubricants, such as hydrogenated vegetable oil, a hydrophobic material. Claim 21 

simply requires the inclusion of a hydrophobic material, 

irrespective of its function. That Kao’s alleged purpose for 

incorporating a hydrophobic material into the claimed 
24 IN RE KAO, IN RE KAO, IN RE AHDIEH

formulation differs from Maloney’s is irrelevant when 

Kao’s alleged purpose is not a limitation of claim 21. 

This court again agrees with the Office. Substantial 

evidence supports the Board’s finding that Maloney 

teaches a controlled release formulation using both hydrophobic and hydrophilic materials, as required by claim 

21. Kao’s argument is wholly without merit because 

Maloney expressly recites adding hydrogenated vegetable 

oil to the formulation, which Kao’s own specification 

states is a hydrophobic material. 

B. Secondary Considerations 

Endo argues that it presented sufficient evidence of 

secondary considerations to overcome the Board’s finding 

of obviousness. Endo’s evidence of secondary considerations and the Board’s response are identical between each 

of the three patent applications related to controlledrelease tablets containing the drug oxymorphone and are 

addressed more fully above. Here, as with the ’432 Application, the Board erred by failing to consider Endo’s 

evidence of secondary considerations. Unlike the ’432 

Application, however, the Board, in this appeal, presented 

a strong showing of obviousness. Indeed, the only claim 

element not expressly disclosed in the prior art was the 

previously-unknown, yet inherent, food-effect property. 

As stated above, merely discovering and claiming a new 

benefit of an old process cannot render the process again 

patentable. Endo’s evidence of secondary considerations 

was insufficient to overcome this strong showing of primary considerations that rendered the claims at issue 

invalid. See, e.g., Leapfrog Enters., Inc. v. Fisher-Price, 

Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007). 
IN RE KAO, IN RE KAO, IN RE AHDIEH 25

II. The ’740 Application 

The Board determined that Ahdieh failed to separately argue the patentability of claims 25 and 30 of the 

’740 Application, and so it determined the patentability of 

all claims based on claim 21. Ahdieh cites three statements in his brief to the Board as showing a separate 

patentability argument regarding claims 25 and 30. 

Reply Br. of Ahdieh at 20 n.7. Far from showing distinct 

arguments for each claim, these fragments show that 

Ahdieh argued all the claims together. Because Ahdieh 

failed to argue to the Office that claim 25 is separately 

patentable, and fails to argue here that claim 30 is separately patentable, the only relevant claim before this 

court in this appeal is independent claim 21. 

A. Obviousness 

 It is undisputed that Maloney discloses a method of 

providing extended pain relief by the provision of a therapeutically effective amount of controlled release oxymorphone. Ahdieh’s asserted novel contribution is “providing 

information” about a previously undiscovered correlation 

between renal failure and bioavailability. Ahdieh argues 

that the Board and the examiner erred in holding his 

claim obvious because there was not substantial evidence 

that the correlation was known in the prior art. 

 This court squarely rejected a similar argument in 

King Pharmaceuticals. There, the claim at issue recited 

“a method of increasing the oral bioavailability of metaxalone” by “administering to the patient a therapeutically 

effective amount of metaxalone in a pharmaceutical 

composition with food,” and “informing” the patient that 

taking metaxalone with food will increase the drug’s 

bioavailability. King Pharms., 616 F.3d at 1270-71. This 

court stated that the relevant question in determining 
26 IN RE KAO, IN RE KAO, IN RE AHDIEH

whether the method claims were patentable was “whether 

the additional instructional limitation of claim 21 has a 

‘new and unobvious functional relationship’ with the 

known method of administering metaxalone with food.” 

Id. at 1279 (citing In re Ngai, 367 F.3d 1336, 1338 (Fed. 

Cir. 2004)). We held that there was no functional relationship between the informing step and the administering step, because “[i]nforming a patient about the benefits 

of a drug in no way transforms the process of taking the 

drug with food,” and therefore the claim was invalid as 

anticipated by the prior art. Id.

 This case is not meaningfully distinct. Though the 

correlation between the renal impairment and bioavailability was not known, informing someone of the correlation cannot confer patentability absent a functional 

relationship between the informing and administering 

steps. In re Ngai, 367 F.3d at 1338; see also General Elec. 

Co. v. Jewel Incandescent Lamp Co., 326 U.S. 242, 249 

(1945) (“It is not invention to perceive that the product 

which others had discovered had qualities they failed to 

detect.”). Just as in King Pharmaceuticals, the informing 

step does not “transform[] the process of taking the drug.” 

616 F.3d at 1279. This is because there is no requirement 

in the claim that the dosage be adjusted in response to the 

informing step. Indeed, because there is no indication of 

who is to be informed or to whom the drug is to be administered, the claim would presumably cover a situation 

where a doctor informs patient A of the correlation and 

administers a therapeutically effective dose of controlled 

release oxymorphone to patient B. Because there is no 

functional relationship between the two steps in the 

method, and because the administration of controlled 

release oxymorphone is squarely present in the prior art, 

Ahdieh’s claim must fail. We agree with our predecessor 

court that to allow such a claim would effectively “remove 

from the public that which is in the public domain by 

virtue of its inclusion in, or obviousness from, the prior 
IN RE KAO, IN RE KAO, IN RE AHDIEH 27

art.” In re Wiseman, 596 F.2d 1019, 1023 (CCPA 1979); 

see also In re Ngai, 367 F.3d at 1339 (noting that allowing 

claims where the printed matter was the only novel 

contribution would allow “anyone [to] continue patenting 

a product indefinitely provided that they add a new 

instruction sheet to the product”). 

 Endo attempts to limit King Pharmaceuticals to the 

anticipation context, and distinguish it because the “informing” step was itself in the prior art, unlike the “providing information” step here. The King Pharmaceuticals

analysis is not so limited. Claim 5 of United States 

Patent Number 6,683,102 was rejected as obvious in King 

Pharmaceuticals, though it depended upon a claim that 

was rejected for anticipation under the above reasoning. 

616 F.3d at 1280-81. Moreover, it is simply not true that 

the correlation in King Pharmaceuticals was itself known 

in the prior art. See id. at 1278 (“Eon tacitly concedes 

that the district court never expressly found the ‘informing’ limitation disclosed in the prior art.”). 

 Endo also argues that the “providing information” 

step and the administration step are functionally related 

because the step of “providing a therapeutically effective 

amount” “of necessity, requires adjusting the dosage as 

appropriate in accordance with the information provided 

in the prior step in light of the patient’s renal condition.” 

Br. of Appellant at 29. However, nothing in the claim

requires that the dosage be adjusted in response to the 

providing of the information. Indeed, there is nothing in 

the claim even referencing the actual condition of the 

patient’s renal system, which would presumably be the 

basis of any adjustment. Endo invites this court to import 

from the specification into the claim the limitation that 

the dosage be adjusted as a result of the informing step. 

This court declines Endo’s invitation. The claim calls 

merely for informing someone of the noted correlation, 

and administering an effective dose of controlled release 
28 IN RE KAO, IN RE KAO, IN RE AHDIEH

oxymorphone to someone. There is no functional relationship between the two steps. 

B. Secondary Considerations 

 Endo argues that the commercial success and unexpected results of Endo’s Opana® ER product overcome the 

showing of obviousness. There is no dispute that Opana®

ER is an embodiment of the claimed invention. 

 The Board assumed that the secondary considerations 

would be enough to overcome a prima facie case of obviousness but held that because Opana® ER was a single 

embodiment of the broad claim, the secondary considerations were not commensurate with the scope of the claim. 

 As discussed above, the Board’s application of so strict 

a commensurateness requirement was improper. However, here, this error was harmless because there was no 

nexus between the secondary considerations presented 

and the claimed invention. See Tokai, 632 F.3d at 1369. 

 The only limitation not expressly recited in the prior 

art of record is the informing step. Endo does not contend 

that the evidence of unexpected results in the form of the 

multiple peaks is at all related to the informing step of 

the claim. Likewise, there is no indication that Opana®

ER’s commercial success is attributable to the informing 

step, particularly because, as discussed above, the claim 

does not require that the informing step have any appreciable effect on the administration of the drug. 

 Because here Endo has not provided any evidence of 

secondary considerations with a nexus to the novel components of claim 21, the secondary considerations do not 

compel a holding of nonobviousness. 
IN RE KAO, IN RE KAO, IN RE AHDIEH 29

CONCLUSION

For the foregoing reasons, this court vacates the decision of the Board in Appeal No. 2010-1307 regarding the 

’432 Application and remands for further proceedings 

consistent with this opinion, and affirms the decisions of 

the Board in Appeal No. 2010-1308 regarding the ’859 

Application and in Appeal No. 2010-1309 regarding the 

’740 Application. 

VACATED AND REMANDED AS TO THE ’432

APPLICATION 

AFFIRMED AS TO THE ’859 AND ’740

APPLICATIONS

COSTS

Each party shall bear its own costs.