Rolls-Royce v. United Technologies Corp. (CAFC 2009-1307) precedential

Giving the fan blade a spin -

The technology in Rolls-Royce's '077 patent and UTC's '931 application relates to swept fan blades used on turbofan jet engines. The fan generally consists of a cascade of fan blades that are attached to, and extend radially outward from, a central rotatable hub. The fan blades rotate around the hub to provide propulsive thrust to air entering the engine by increasing the pressure and momentum of that air. A cylindrical-shaped cover, known as a casing, encloses the fan and the rest of the engine.

Shockwaves contribute to engine noise and cause inefficiencies. This technology addresses two types of shock: endwall shock and passage shock. Endwall shock arises when pressure waves reflect off the engine casing and into the air flow. Passage shock arises from the supersonic flow of air over the fan blades. UTC's '931 application notes that the leading edge of the fan blade creates passage shock upon initial contact with the air flow. Endwall shock and passage shock bear no relation to each other and, in fact, arise in different places within the fan.

To reduce shockwaves, the prior art teaches to sweep blades either rearward or forward. A blade bent toward the relative velocity vector is swept forward; a blade bent away from the relative velocity vector is swept rearward. The relative velocity vector is the magnitude and direction of the air flow that hits the leading edge of a fan blade. The relative velocity vector is a combination of axial and circumferential air flow. The axial air flow is the flow of air toward the engine as it engages air along its path during flight. The circumferential air flow is the flow of air in the direction of the rotation of the blades caused by the blades themselves.

The sweep angle measures the degree of sweep in a blade. Again, these angles may incline forward or rearward. In a forward sweep angle, the blade bends toward the relative velocity vector. In a rearward sweep angle, the blade bends away from the relative velocity vector. The sweep angle at any point on a fan blade leading edge is a function of the relative velocity vector and the leading edge shape at that point.

On appeal -

UTC appeals the district court's claim construction and finding of no interference-in-fact based on obviousness. UTC and Rolls-Royce have stipulated that obviousness, not anticipation, is responsible for the interference-in-fact. This court has jurisdiction under 28 U.S.C. § 1295(a)(1) and 28 U.S.C. § 1295(a)(4)(C).

In an appeal of a 35 U.S.C. § 146 action, this court "review[s] the district court's factual findings for clear error and its conclusions of law de novo . . . ." Winner Int'l Royalty Corp. v. Wang, 202 F.3d 1340, 1344-45 (Fed. Cir. 2000). The purpose of a patent interference proceeding is to determine whether two parties claim the same patentable invention, and if so, who under the law is entitled to priority of invention. See Noelle v. Lederman, 355 F.3d 1343, 1350 (Fed. Cir. 2004). An interference-in-fact "exists if the subject matter of a claim of one party would, if prior art, have anticipated or rendered obvious the subject matter of a claim of the opposing party and vice versa." 37 C.F.R. § 41.203(a); see Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1161 (Fed. Cir. 2006).

This court gives pending claims in interference proceedings their broadest reasonable construction in light of the specification. See Genentech, Inc. v. Chiron Corp., 112 F.3d 495, 499 (Fed. Cir. 1997); 37 C.F.R. § 41.200(b). This court will uphold any reasonable interpretation of disputed claim language by the PTO. See In re Morris, 127 F.3d 1048, 1055 (Fed. Cir. 1997).

The portion of claim 23 of the '931 application at issue is:

the outer region being translated forward relative to a leading edge with the same sweep angle as an outward boundary of the intermediate region to provide a sweep angle that causes the blade to intercept the shock.

'931 application claim 23 (emphases added). The claim terms requiring construction are "translated forward" and "a sweep angle that causes the blade to intercept the shock."

Claim Construction

The CAFC had a variation of the district court's construction for "translated forward."

The district court construed "translated forward" to mean "moved axially forward in the direction of the working medium."

The plain language of "translated forward" means moved toward the forward direction, but the claim language does not designate a clear "forward" direction. The district court found that one of ordinary skill in the art would necessarily have consulted the specification to learn the meaning of "translated forward." The district court also found no use of the term "translation" in the industry or in any prior art other than the related '985 patent.

As the claim language does not clearly state the directional tilt of the outer region, this court as well consults the specification. Based on that source, this court construes "translated forward" to mean "moved forward toward the axial direction."

This was, of course, narrower than UTC would have it. The CAFC characterized UTC's suggested construction as follows:

This court considers unreasonable an interpretation that allows that term to cover two directions at right angles to each other.

In sum, this court declines to unreasonably broaden a specific claim term based on questionable prosecution history when the specification requires a particular construction.

"Sweep angle" at the CAFC also met with modest variance from the district court.

The district court construed "a sweep angle that causes the blade to intercept the shock" to mean "a sweep angle in the outer region that is constant or decreasing." It further explained that this construction does not include forward sweep. The plain language of "a sweep angle that causes the blade to intercept the shock" leaves the properties of that claimed angle unclear. The district court found that one of ordinary skill in the art would have necessarily resorted to the specification to interpret "a sweep angle that causes the blade to intercept the shock."

This court construes "a sweep angle that causes the blade to intercept the shock" to mean "a rearward sweep angle in the outer region that is constant or decreasing" because the specification supports only rearward sweep.

Because the invention of the '931 application specifies a nonincreasing sweep angle with increasing radius, this example shows that the invention did not contemplate forward sweep in the outer region.

This court construes "a sweep angle that causes the blade to intercept the shock" from the point of view of a person of ordinary skill in the art. See Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005) ("It is the person of ordinary skill in the field of the invention through whose eyes the claims are construed.").

UTC's lawyers again demonstrated being directionally challenged.

If, as UTC suggests, a negative sign could indicate forward sweep, then translating the outer region from forward sweep to zero sweep would be increasing--a direct contradiction of the requirements of the specification.

Interference / Obviousness

Interference necessarily involves obviousness at the least (anticipation being stronger tea).

An interference-in-fact "exists if the subject matter of a claim of one party would, if prior art, have anticipated or rendered obvious the subject matter of a claim of the opposing party and vice versa." 37 C.F.R. § 41.203(a); see Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1161 (Fed. Cir. 2006). If claim 8 of Rolls-Royce's '077 patent would not have been obvious to one of skill in the art in view of claim 23 of UTC's '931 application, then this record does not show a cause for interference. See Medichem, 437 F.3d at 1161.

Obviousness is a question of law based on underlying factual inquiries including: (1) the scope and content of the prior art; (2) the level of ordinary skill in the art; (3) the differences between the prior art and the claimed invention as perceived before the time of invention; and (4) the extent of any objective indicia of non-obviousness. Monarch Knitting Mach. Corp. v. Sulzer Morat GMBH, 139 F.3d 877, 881 (Fed. Cir. 1998). This court reviews a district court's ultimate determination of obviousness without deference, while reviewing the underlying factual inquiries for clear error. Weatherchem Corp. v. J.L. Clark, Inc., 163 F.3d 1326, 1331 (Fed. Cir. 1998). If a person of ordinary skill, before the time of invention and without knowledge of that invention, would have found the invention merely an easily predictable and achievable variation or combination of the prior art, then the invention likely would have been obvious. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 417, 421 (2007). To preclude hindsight in this analysis, this court flexibly seeks evidence from before the time of the invention in the form of some teaching, suggestion, or even mere motivation (conceivably found within the knowledge of an ordinarily skilled artisan) to make the variation or combination. See Ortho-McNeil Pharm., Inc. v. Mylan Labs., Inc., 520 F.3d 1358, 1363-65 (Fed. Cir. 2008); Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1346-53 (Fed. Cir. 2008); Takeda Chem. Indus., Ltd. v. Alphapharm Pty., Ltd., 492 F.3d 1350, 1355-63 (Fed. Cir. 2007).

UTC tried to make the leap to its fan blade having forward sweep, but the divergence was too steep.

For the interference analysis, UTC's '931 application is prior art for Rolls-Royce's '077 patent. This court applies the district court's standard of ordinary skill in the art. Under this court's claim construction, UTC's '931 application does not disclose "an outer region between the intermediate region and the fan casing, the outer region defining a forward sweep angle" as required by claim 8 of the '077 patent.

UTC argues that forward sweep in the outer region would have been an easily predictable and achievable variation in view of the disclosure of rearward sweep in UTC's '931 application.

Not so.

[T]he record contained no evidence that would have suggested to or motivated an ordinarily skilled artisan to sweep the fan blade forward in the outer region. Thus, the record supports the district court's conclusion that this variation would not have been obvious.

Based on the same evidence, UTC argues that an ordinarily skilled artisan would have found it obvious to try to reverse the sweep angle from rearward to forward sweep in the outer region in order to intercept the endwall shock. To determine that an invention would have been obvious to try on the basis of the record before the time of invention, this court has clarified, with respect to inventions requiring selection of a species from a disclosed genus, that the possible approaches and selection to solve the problem must be "known and finite." See Abbott, 544 F.3d at 1351 (holding as conditions in which "obvious to try" may negate patentability, "the problem is known, the possible approaches to solving the problem are known and finite, and the solution is predictable through use of a known option"). The important question is whether the invention is an "identified, predictable solution" and an "anticipated success." See id. at 1352. In this case, the broad selection of choices for further investigation available to a person of ordinary skill included any degree of sweep. See Takeda, 492 F.3d at 1359 (holding the invention not obvious to try because the prior art disclosed a broad selection of compounds that an ordinarily skilled artisan could have selected for further investigation). Also, the record does not show that one of ordinary skill in the art would have any reason to try forward sweep in the outer region at all. A particular course or selection is not obvious to try unless some design need or market pressure or other motivation would suggest to one of ordinary skill to pursue the claimed course or selection. See KSR, 550 U.S. at 421. In other words, one of ordinary skill must have "good reason to pursue the known options within his or her technical grasp." See id. Because one of ordinary skill could not use CFD simulations to detect endwall shock and no other evidence in the record gives a reason to reverse the sweep angle to intercept that shock, Rolls-Royce's invention would not have presented itself as an option at all, let alone an option that would have been obvious to try.

Secondary considerations swept away any lingering doubts.

In the obviousness analysis, secondary considerations are often some of the best "independent evidence of nonobviousness." Ortho, 520 F.3d at 1365. The secondary considerations in this case reinforce and substantiate the district court's correct conclusion of non-obviousness. The district court found that Rolls-Royce's invention fulfilled a long-felt but unresolved need, achieved commercial success, and also received industry acclaim from the inventor's peers.

To establish commercial success of the Rolls-Royce invention, Rolls-Royce was required to establish a nexus between the commercial success and the patentably distinct feature of the invention. See Winner Int'l Royalty Corp., 202 F.3d at 1350-51. The district court found that the highly swept fan blades feature was strongly marketed to the airlines. The court found that the improved efficiency and noise characteristics of the fan blade were a major driving force behind the sales of the Rolls-Royce engines that incorporate them. The district court did not clearly err in its secondary consideration findings. Therefore, Rolls-Royce established the required nexus between engine sales and the invented fan blade design. The secondary considerations cement the district court's conclusion of non-obviousness.

Affirmed.