Opinion of the court filed by Circuit Judge RADER. Dissenting-in-part opinion filed by Circuit Judge NIES.
RADER, Circuit Judge.
King Instrument Corporation (King) sued Luciano Perego and Tapematic SrL (Tape-[944]*944matic) for infringement of U.S. Patents Nos. 3,637,153 (the 153 patent), 3,825,461 (the ’461 patent), and 3,997,123 (the 123 patent). The United States District Court for the District of Massachusetts awarded King damages for Tapematic’s infringement of the ’461 patent. King Instrument Corp. v. Perego, 737 F.Supp. 1227, 1242, 16 USPQ2d 1994, 2007 (D.Mass.1990) (King). The district court found that Tapematic did not infringe the 153 patent or the 123 patent. Id. at 1242-43. Finding no clear error in the district court’s infringement analysis, and no abuse of discretion in the district court’s assessment of the amount of damages, this court affirms.1
BACKGROUND
King’s three patents relate to loading magnetic audio or video tape into closed cassettes. A fully loaded cassette contains two types of tape: the magnetic audio or video tape and a non-magnetic leader tape. The magnetic tape — also called “use” tape — functions to permit customers to record or play back recordings. The non-magnetic leader tape — a short length of plastic, often clear, tape — leads both ends of the magnetic tape. One end of the leader tape attaches to the winding hub of the cassette; the other end attaches to the magnetic tape.
The manufacturer produces closed tape cassettes without any magnetic tape. Each closed cassette contains only a leader tape connected to its two winding hubs. The manufacturer adds magnetic tape later by splicing magnetic tape into the middle of the leader tape and winding it into the cassette. King and Tapematic market competing machines that automatically splice and wind magnetic tape into otherwise completed video cassettes.
The ’153 Patent
The ’153 patent discloses a partially automated machine for loading magnetic tape into a cassette. The ’153 patent claims a mechanical splicing block whose arms swing to bring the magnetic tape into contact with the leader tape.
The invention of the ’153 patent manually extracts the leader tape from the cassette and places it over a splicing head. A vacuum holds the leader tape in place while a knife cuts it into two sections. At this point, the moveable track swings out of alignment with the stationary track. A second moveable track holding the magnetic tape then swings into alignment with the leader tape. The invention applies a splice between the leader tape and the magnetic tape which are held in place by a vacuum. The vacuum then releases the tape and the machine turns the hub to load magnetic tape into the cassette. When the cassette is full, the vacuum again grabs and a knife cuts the magnetic tape. The swinging arm brings the end of the magnetic tape back in contact with the other end of the leader tape and applies a splice. The hubs tighten the tape in the cassette to complete the loading.
The ’123 Patent
The 123 patent claims a winding machine which more fully automates the invention disclosed in the 153 patent. Instead of loading cassettes one at a time, the invention of the 123 patent enables an operator to load a stack of cassettes (e.g., 20 to 30) into a cassette magazine. The magazine advances each cassette in sequential order for loading by the 153 patent device. The 123 patent also claims a mechanism for automatically extracting the leader tape from the cassette and positioning it on the splicing blocks. The 123 patent’s invention thus automates the 153 patent’s manual extraction and positioning functions.
The ’461 Patent
The ’461 patent claims a splicing assembly for connecting the magnetic and leader tapes. [945]*945The splicing assembly includes three splicing blocks. Two of the three blocks shift to align the magnetic tape with the leader tape; the third is a stationary splicing block.
The District Court
The district court found that Tapematic infringed the ’461 patent and awarded King damages. King, 737 F.Supp. at 1242. The district court did not find willful infringement. Id. at 1241. The district court also upheld the validity of the T53 patent, id. at 1230, but found that Tapematic did not infringe, literally or under the doctrine of equivalents, either the ’153 or the 123 patent. Id. at 1234, 1239, 1241.
King appeals the district court’s findings of noninfringement of the 153 and 123 patents and seeks enhanced damages for willful infringement of the 153 patent. Tapematic cross-appeals the trial court’s infringement finding on the ’461 patent and challenges the damages award. Tapematic does not appeal the trial court’s validity findings on the 153 patent.
Appellate History
This panel heard oral argument on the cross-appeals on August 5, 1991. More than two years later, on January 13, 1994, the court decided sua sponte to consider this appeal en banc. The court then deferred action on this appeal pending en banc resolution of Rite-Hite Corp. v. Kelley Co., an appeal brought in 1992 involving damages issues overlapping with those raised by Tape-matie. On June 15,1995, the court issued its opinion in Rite-Hite resolving the damages issues. Rite-Hite Corp. v. Kelley Co., 56 F.3d 1538, 35 USPQ2d 1065 (Fed.Cir.1995) (en banc). On July 10, 1995, the court returned the present appeal to this panel for disposition in accordance with Rite-Hite.
DISCUSSION
This court reviews the district court’s findings of fact under Fed.R.Civ.P. 52(a):
Findings of fact, whether based on oral or documentary evidence, shall not be set aside unless clearly erroneous, and due regard shall be given to the opportunity of the trial court to judge of the credibility of the witnesses.
See Heisig v. United States, 719 F.2d 1153, 1158 (Fed.Cir.1983). Legal conclusions of the district court stand unless incorrect as a matter of law. Id.
This court does not review de novo proceedings of the district court. Medtronic, Inc. v. Daig Corp., 789 F.2d 903, 904, 229 USPQ 664, 666 (Fed.Cir.), cert. denied, 479 U.S. 931, 107 S.Ct. 402, 93 L.Ed.2d 355 (1986). The party seeking reversal of a district court decision bears the burden of showing reversible legal error or clear factual errors in light of the trial record. Carl Schenck, A.G. v. Nortron Corp., 713 F.2d 782, 785, 218 USPQ 698, 700 (Fed.Cir.1983). Where the record viewed in its entirety renders the district court’s account of the evidence plausible or discloses two permissible readings of the evidence, the fact-finder has committed no clear error. Hybritech Inc. v. Monoclonal Antibodies, Inc., 802 F.2d 1367, 1375, 231 USPQ 81, 87 (Fed.Cir.1986), cert. denied, 480 U.S. 947, 107 S.Ct. 1606, 94 L.Ed.2d 792 (1987).
I. Infringement
The district court assessed infringement using the standard tests. See King, 737 F.Supp. at 1231 (citing Standard Oil Co. v. American Cyanamid Co., 774 F.2d 448, 452, 227 USPQ 293, 295-96 (Fed.Cir.1985); Martin v. Barber, 755 F.2d 1564, 1567, 225 USPQ 233, 234 (Fed.Cir.1985)). All three King patents contain “means-plus-function” language. King, 737 F.Supp. at 1231. This court construes means-plus-function claim language “to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.” 35 U.S.C. § 112 (1988); Valmont Indus., Inc. v. Reinke Mfg. Co., 983 F.2d 1039, 1042, 25 USPQ2d 1451, 1454 (Fed.Cir.1993); Johnston v. IVAC Corp., 885 F.2d 1574, 1580, 12 USPQ2d 1382, 1386 (Fed.Cir.1989). Thus, for a means-plus-function limitation to read on an accused device, the accused device must employ means identical or equivalent to the structures, material, or acts described in the patent specification. The accused device must also perform the identical function as [946]*946specified in the claims. Valmont, 983 F.2d at 1042.
A.The ’133 Patent
The district court held that Tapematic did not infringe the ’153 patent. King, 737 F.Supp. at 1242-43. The district court found that the accused device aligns and splices tape differently than the claimed structure. Id. at 1233. Tapematic’s accused machines used a horizontal shift block assembly to align and splice. The trial court found that this shift block device did not literally infringe the T53 patent’s swing arm claims. Id. at 1234. Moreover the accused device operates in such a different “way” that the district court found no infringement under the doctrine of equivalents. Id. at 1239.
Specifically, the district court noted several differences between the ’153 claims and the accused device. For instance, the ’153 patent claims a swing arm assembly which pivots in a single plane; the accused Tapematic device’s shift block assembly slides in two planes. The ’153 patent discloses three separate splicing blocks, one fixed and two pivoting; the accused device uses only two splicing blocks, one fixed and the other sliding. Finally, the trial court cited testimony by E. Blanco (Tapematic’s expert), W. Isom (King’s expert), and J. King (inventor of the 153 patent), who all agreed that the accused product worked differently than the claimed device. Id. at 1234. In performing its infringement analysis, the trial court correctly construed claim 16 in connection with the specification to include the pivoting swing arm assembly. The trial court correctly interpreted claims 2, 10, and 16 to encompass the structure disclosed in the specification for holding, aligning, and splicing tapes — and equivalents thereof.
After comparing the claimed device with the accused product, the court correctly determined that the 153 patent was not infringed — either literally or under the doctrine of equivalents. Id. at 1234, 1239. Moreover, the district court’s finding of non-infringement of the 153 patent is consistent with this court’s earlier decision in King Instrument Corp. v. Otari Corp., 767 F.2d 853, 226 USPQ 402 (Fed.Cir.1985) (Otari), cert. denied, 475 U.S. 1016, 106 S.Ct. 1197, 89 L.Ed.2d 312 (1986), which based a finding of infringement upon a disclosure of the Otari mechanism in the patent specification. See King, 737 F.Supp. at 1233 n. 6. Because it affirms the district court’s finding of nonin-fringement on the 153 patent, this court need not address willfulness and enhanced damages on that patent.
B. The ’123 Patent
The district court also held that Tape-matic did not infringe the 123 patent. King, 737 F.Supp. at 1242-43. The district court compared the claims of the 123 patent with each of the Tapematic accused devices (Tapematic 900, 2,002, and 3,000 Series). See id. at 1237. The district court found that the leader extracting and positioning mechanisms in the Tapematic machines operate very differently from that recited in the 123 patent claims. Id. Specifically, claims 1 and 12 of the 123 patent claim a single mechanism to extract and position the leader tape in a single movement. The Tapematic machines, on the other hand, have at least two different components performing these tasks in a substantially different way. The 123 patent described extraction of the leader tape with a vacuum device. Tapematic’s devices use a mechanical extractor. Therefore, the district court correctly concluded that the Tapematic machines did not literally, nor under the doctrine of equivalents, infringe the 123 patent. Id. at 1237-39.
C. The %61 Patent
Although finding no literal infringement of claim 1 of the ’461 patent, King, 737 F.Supp. at 1235, the district court found that the splicer in the Tapematic 2,002’s reel changer literally infringed claim 12. Id. at 1235-36. The Tapematic 2,002 is a “dual pancake” loader, i.e., it includes a reel changer assembly that automatically switches to a second reel of magnetic tape when the first reel runs out. Tapematic’s reel changer spliced magnetic tape to magnetic tape. Because claim 1 includes only a structure for splicing magnetic tape to leader tape, the district court determined that Tapematic’s assembly did not literally infringe claim 1. [947]*947Claim 12, however, contained no such limitation. Moreover, claim 12 does not require alignment of “abutting” ends of the leader and magnetic tapes.
The district court properly found infringement of claim 12 because all limitations of claim 12 read on the splicing assembly of the Tapematic 2,002’s reel changer. Id. at 1236. Therefore, this court affirms the district court’s finding that Tapematic infringed the ’461 patent.
II. Lost Profits
The district court found that Tape-matic infringed the ’461 patent. The district court found that this infringement caused King to sustain economic injury in the form of lost profits. In other words, “but for” the infringement, King would have sold more of its competing product. See Otari, 767 F.2d at 863; Paper Converting Mach. Co. v. Magna-Graphics Corp., 745 F.2d 11, 21, 223 USPQ 591, 598 (Fed.Cir.1984). The district court also took into account that King’s competing product did not embody the invention of the ’461 patent asserted against Tapematic. The district court, however, found reason to redress King’s injury notwithstanding King’s election to refrain from making or selling the patented invention. Tapematic challenges the award of lost profits in such an instance, alleging instead that lost profits can be awarded only to one who makes or sells the patented device.
This court must reject Tapematic’s challenge. This court held in Rite-Hite, sitting en banc, that a patent owner who has suffered lost profits is entitled to lost profits damages regardless of whether the patent owner has made, used, or sold the patented device. See Rite-Hite, 56 F.3d at 1546, 35 USPQ2d at 1072.2 Furthermore, the language and history of the patent act and sound policy require this result, as demonstrated in the following analysis.
A. The Patent Act — Language and History
Title 35 of the United States Code provides that a patent grant confers “the right to exclude others from making, using, or selling the invention.” 35 U.S.C. § 154(a)(1) (West Supp.1995) (emphasis added). An act of infringement — i.e., making, using, or selling the patented invention “without authority,” 35 U.S.C. § 271(a) (1988) — trespasses on this right to exclude. Title 35 redresses such a violation of rights by “award[ing] the claimant damages adequate to compensate for the infringement.” 35 U.S.C. § 284 (1988).
Section 284 imposes no limitation on the types of harm resulting from infringement that the statute will redress. The section’s broad language awards damages for any injury as long as it resulted from the infringement. Though this section sets a lower limit of a reasonable royalty on the amount of recovery, it mandates an amount “adequate to compensate for the infringement.” Id. The Patent Act also includes enhanced damages for willful infringement or bad faith and for attorney fees. 35 U.S.C. §§ 284, 285 (1988); see Beatrice Foods Co. v. New England Printing & Lithographing Co., 923 F.2d 1576, 1578, 17 USPQ2d 1553, 1555 (Fed.Cir.1991).
Section 284 specifies that compensation takes the form of “damages.” Congress and the Supreme Court have had several opportunities to define and construe this term under the Patent Act and section 284. Congress has not amended the Patent Act, nor has the Supreme Court interpreted the term “damages” to require exploitation of the invention as a prerequisite to recovery of lost profits. Moreover, such a prerequisite runs contrary to the language and enactment history of section 284.
The long history of the Patent Act shows that its language does not require a patentee to make the patented invention to qualify for damages. Before 1946, a patentee who proved infringement could recover “in addition to the profits to be accounted for by the [948]*948defendant, the damages the complainant has sustained thereby.” R.S. § 4921. Thus a patentee could recover “both [its] own damages and the infringer’s profits.” General Motors Corp. v. Devex Corp., 461 U.S. 648, 654, 103 S.Ct. 2058, 2062, 76 L.Ed.2d 211, 217 USPQ 1185, 1188 (1983). The law changed in 1946 to provide a recovery of “general damages which shall be due compensation for making, using, or selling the invention.” Act of August 1, 1946, ch. 726, 60 Stat. 778, 35 U.S.C. § 70 (1946).
The 1946 amendment eliminated the paten-tee’s right to recover the infringer’s “profits as such and allow recovery of damages only.” Aro Mfg. Co. v. Convertible Top Replacement Co., 377 U.S. 476, 505-07, 84 S.Ct. 1526, 1542-43, 12 L.Ed.2d 457, 141 USPQ 681, 693-94 (1964); General Motors, 461 U.S. at 654, 103 S.Ct. at 2061-62. These profits were considered too difficult and cumbersome to prove in court. See H.R.Rep. No. 1587, 79th Cong., 2d Sess. 1-2 (1946); S.Rep. No. 1503, 79th Cong., 2d Sess. 2 (1946). The 1946 amendment thus sought to eliminate the delay and cost of protracted litigation to determine the infringer’s profits. Id.
The 1946 amendment, however, retained the guarantee of complete compensation for the damages from infringement. The statutory language of the 1946 amendment anticipated the requirement for “adequate” compensation in the present statute. See 35 U.S.C. § 284; see also H.R.Rep. No. 1587, 79th Cong., 2d Sess. 1 (1946). To expedite the legal process, Congress amended the statute to provide for “any damages the complainant can prove.” Id.3 Later, the Patent Act of 1952 consolidated the existing provisions relating to damages into section 284. The 1952 Act effected no substantive change other than the addition of an attorney fees clause. General Motors, 461 U.S. at 655 n. 9, 103 S.Ct. at 2062 n. 9.
The Supreme Court has reinforced the breadth of section 284 in two cases interpreting the statutory provision. In General Motors, the more recent case, the Court held that section 284 provided for the award of prejudgment interest “where necessary to afford the plaintiff full compensation for the infringement.” 461 U.S. at 654, 103 S.Ct. at 2062. Discussing the 1946 amendment, the Supreme Court stated: “Congress sought to ensure that the patent owner would in fact receive full compensation for ‘any damages ’ he suffered as a result of the infringement.” Id. at 654-55, 103 S.Ct. at 2062 (quoting H.R.Rep. No. 1587, 79th Cong., 2d Sess. 1-2 (1946)) (emphasis added).
And in Aro, the Court’s first interpretation of section 284, the Court read the term “damages” broadly to cover any pecuniary injuries:
[T]he present statutory rule is that only “damages” may be recovered. These have been defined by this Court as “compensation for the pecuniary loss he [the paten-tee] has suffered from the infringement, without regard to the question whether the defendant has gained or lost by his unlawful acts.” Coupe v. Royer, 155 U.S. 565, 582 [15 S.Ct. 199, 206, 39 L.Ed. 263], They have been said to constitute “the difference between his pecuniary condition after the infringement, and what his condition would have been if the infringement had not occurred.” Yale Lock Mfg. Co. v. Sargent, 117 U.S. 536, 552 [6 S.Ct. 934, 942, 29 L.Ed. 954], The question to be asked in determining damages is “how much had the Patent Holder and Licensee [949]*949suffered by the infringement. And that question [is] primarily: had the Infringer not infringed, what would the Patent Holder-Licensee have made?” Livesay Window Co. v. Livesay Industries, Inc., supra, 251 F.2d [469] at 471 [5th Cir.1958].
Aro, 377 U.S. at 507, 84 S.Ct. at 1543 (emphasis added; second and third alterations in original); see Panduit Corp. v. Stahlin Bros. Fibre Works, Inc., 575 F.2d 1152, 1156, 197 USPQ 726, 729 (6th Cir.1978) (quoting Aro).
By using the phrase “damages adequate to compensate,” the Act provides economic redress sufficient to restore the paten-tee to its rightful position absent the infringement. 35 U.S.C. § 284. The Supreme Court has underscored this meaning of section 284. Similarly, construing section 284, this court held: “If the record permits the determination of actual damages, namely, the profits the patentee lost from the infringement, that determination accurately measures the patentee’s loss.” Hanson v. Alpine Valley Ski Area, Inc., 718 F.2d 1075, 1078, 219 USPQ 679, 681 (Fed.Cir.1983); see also Weinar v. Rollform Inc., 744 F.2d 797, 807, 223 USPQ 369, 375 (Fed.Cir.1984), cert. denied, 470 U.S. 1084, 105 S.Ct. 1844, 85 L.Ed.2d 143 (1985).
Section 284 provides adequate compensation for the infringement of rights. The nature of the protected rights explains as well the breadth of section 284’s protection. Before the 1952 Act, the Patent Act defined the bundle of patent rights in terms of “the exclusive right to make, use, and vend the invention or discovery.” 35 U.S.C. § 40 (1946). This wording — defining the grant in terms of the right to make the invention, rather than the right to exclude others from making the invention — caused confusion.
The 1952 Act, § 154, clarified that a patent empowered its owner “to exclude others from making, using, or selling” the invention. 35 U.S.C. § 154 (1952) (emphasis added). The 1952 amendment should have corrected any mistaken belief that patent rights somehow hinged upon the patentee’s exploitation of the invention. Inventors possess the natural right to exploit their inventions (subject to the patent rights of others in a dominant patent) apart from any Government grant. Therefore, patent rights do not depend upon the exercise of rights already in the patentee’s possession. Thus, the 1952 Act clarified that a patent confers the right to exclude others from exploiting an invention. It does not confer the right to exploit the invention already possessed by the inventor.
This understanding of the right protected by section 284 informs the purpose and scope of the damages provision. Section 284 protects the right to exclude others from exploiting an invention. To invoke that protection, a patentee need not have exercised its natural right to itself make, use, or sell the invention. The damages section, section 284, protects the right to exclude, not the right to exploit. A patentee qualifies for damages adequate to compensate for infringement without exploiting its patent.
Thus the language, the context, the enactment history, and the Supreme Court’s interpretation of the Patent Act clarify that “damages” in section 284 encompasses an amount necessary to redress any direct injury from infringement. Moreover, the award of damages compensates for the violation of the patentee’s right to exclude others from making, using, or selling the invention. The patentee need not make, use, or sell the invention to sustain an injury to that right.
B. The Patent Act — Policy
A patentee may suffer injury resulting from the violation of its right to exclude infringing, competing products. The most obvious form of injury from such a violation, as mentioned above, is profits lost to the infringer in the market for the product. The patentee’s sale of a competing product not covered by the patent within that market does not change the policy justifications for restoring the parties to the positions they would have occupied absent the infringement.
A patentee is awarded a patent for disclosure of a patentable invention “[t]o promote the Progress of ... useful Arts.” U.S. Const, art I, § 8, cl. 8. A patentee need not make, use, or sell an invention to gain patent protection. Upon proper disclosure of a pro-[950]*950teetable invention, a patentee acquires the right to exclude others from making, using, or selling the invention.
“The encouragement of investment-based risk is the fundamental purpose of the patent grant, and is based directly on the right to exclude.” Patlex Corp. v. Mossinghoff, 758 F.2d 594, 599, 225 USPQ 243, 247 (Fed.Cir.), modified, 771 F.2d 480, 226 USPQ 985 (Fed.Cir.1985). “The federal patent system thus embodies a carefully crafted bargain for encouraging the creation and disclosure of new, useful, and nonobvious advances in technology and design in return for the exclusive right to practice the invention for a period of years.” Bonito Boats, Inc. v. Thunder Craft Boats, Inc., 489 U.S. 141, 150-51, 109 S.Ct. 971, 977, 103 L.Ed.2d 118 (1989).
Thus, the Patent Act creates an incentive for innovation. The economic rewards during the period of exclusivity are the carrot. The patent owner expends resources in expectation of receiving this reward. Upon grant of the patent, the only limitation on the size of the carrot should be the dictates of the marketplace. Section 284 attempts to ensure this result by deterring infringers and recouping market value lost when deterrence fails.
Providing lost profits compensation in this case preserves those constitutional incentives. Moreover, construing section 284 in harmony with the breadth of its language allows the market, rather than courts, to dictate the incentives. This court should not presume to determine how a patentee should maximize its reward for investing in innovation. Yet denying the patentee its provable lost profits in this or any case where the patentee chooses to market a competing non-patented product would have this result.
The market may well dictate that the best use of a patent is to exclude infringing products, rather than market the invention. A patentee, perhaps burdened with costs of development, may not produce the patented invention as efficiently as an infringer. Indeed, the infringer’s presence in the market may preclude a patentee from beginning or continuing manufacture of the patented product. Thus, as apparent in this case, the patentee may acquire better returns on its innovation investment by attempting to exclude infringers from competing with the patent holder’s nonpatented substitute.
Under this situation, the Patent Act is working well. The patentee is deriving proper economic return on its investment in acquiring a patent right. The public benefits from the disclosure of the invention and the ability to exploit it when the patent term expires. As the Supreme Court noted:
Congress, in the choice of means of promoting the useful arts by patent grants, could have provided that the grant should be conditioned upon the use of the patented invention, as in fact it did provide by the Act of 1832.... But Congress was aware that an unpatented invention could be suppressed and the public thus deprived of all knowledge or benefit of it.
Special Equip. Co. v. Coe, 324 U.S. 370, 378, 65 S.Ct. 741, 745, 89 L.Ed. 1006 (1945). Moreover, the government can simply “take” the invention where warranted by public interest concerns and provide “adequate compensation” to the patent holder. 28 U.S.C. § 1498 (1988).
As long as the patentee receives a proper economic return on its investment in the acquisition of a patent, the Act does not require that return to come from the sale of patented products.4 The Act supplies a carrot in the form of economic rewards resulting from the right to exclude. The Act further guarantees adequate damages in the form of provable lost profits to underscore the value of the invention and the incentive to innovate. The Act does not dictate that a patentee must manufacture its own invention to recov[951]*951er the costs of innovation.5
Requiring exploitation of the claimed invention for a recovery of lost profits would cause a systematic failure to award “damages adequate to compensate for the infringement” in cases where the patent holder could otherwise prove causation. Requiring exploitation would force patent owners to accept a reasonable royalty in cases where a reasonable royalty is inadequate compensation. In-fringers would in effect receive the windfall of a retroactive compulsory license from the patent owner.
A hypothetical example shows how an in-fringer could profit from such a rule. A hypothetical patentee could market a product covered by a patent and efficiently supply all demand for the product. A competitor seeking a license under the patent would not succeed. The patentee profits more by supplying the demand itself than by granting a license on terms which would allow the competitor to reasonably operate. In this situation, no reasonable royalty exists. Willing negotiators, assuming they both act in their own best interests, would not agree to any royalty. The value of exercising the right to exclude is greater than the value of any economically feasible royalty. If the competitor infringes in this situation and the paten-tee can recover only a “reasonable royalty,” the patentee does not receive “adequate compensation” as the statute requires. The same reasoning applies anytime the patent owner benefits more by excluding others than by licensing.
In such situations, if lost profits are not available simply because the patent holder does not market a product pursuant to its patent, infringement may actually be profitable. If licensing (rather than excluding) competitors would have proven more rewarding to the patentee, the patentee would have licensed. Instead, the market dictated that exclusion was the best way to recover innovation investments. Limiting the patentee’s recovery to a reasonable royalty, however, would give the infringer what the market denied — a license. Fortunately the Patent Act does not create such incentives to infringe. Rather, it guarantees damages adequate to compensate for infringement— which include provable lost profits.6
Requiring a patentee to exploit the infringed claims as a prerequisite for lost profits damages would also create two significant practical problems. First, the remedy for [952]*952infringement would depend partly on the type and number of claims selected by the inventor, rather than on their scope. Second, infringement trials would become more cumbersome and complex because a patentee would have to prove that the claims cover both its competitor’s product and its own.
A hypothetical again illustrates this problem. An inventor originates a useful, nonob-vious device composed of the elements A, B, C, and Qi. A device consisting of ABC is well known. The addition of Qi is a significant advance. The inventor or someone on the research team knows, however, that element Q2 or element Q3 could function in the device in place of Qj. Because of the different characteristics of the elements Qi, Q2, and Q3, and the different language necessary to describe these elements, the three embodiments are not readily comprehended in a single claim. Thus, in order to cover the subject matter of the three independent claims, ABCQi, ABCQ2, and ABCQ3, three separate patents could issue, perhaps with differing inventive entities. See In re Kaplan, 789 F.2d 1574, 229 USPQ 678 (Fed.Cir.1986) (independently derived best mode created an independently patented invention even though it was described in an earlier patent).
The inventor then markets a device covered by claim ABCQi. Competitors — unable to acquire a license — deliberately market devices which literally infringe claims ABCQ2 and ABCQ3. According to the dissenting opinion, the inventor cannot recover his lost profits for this infringement. The inventor instead must, in effect, grant a compulsory license to willful infringers. Moreover, the infringers have an incentive to infringe to acquire what the market does not supply, a mandatory license.
The potential for increasing the complexity of patent litigation is especially disturbing. The inventor would have to prove that its own product falls under the patent. Infring-ers would escape lost profits and acquire a mandatory license by showing the inventor’s product is not within the claims. The length, cost, and complexity of an infringement trial would conceivably double. The damages phase of a trial would feature an entire new issue of “reverse infringement.” The inventor would have to show that the patent’s claims read on the inventor’s own product, while the infringer would try to show they do not. Once again, as a precondition for lost profits, the parties would parse the claims and call on experts to apply the claim language to an unaccused device.
The language of the 1952 Act did not contemplate creation of an entire new issue of “reverse infringement.” The language of the Patent Act recognizes that the value of a claim to the patentee, and the extent of harm from infringement, do not depend on whether the patentee markets the claimed device. To adequately compensate for infringement of the right to exclude, as section 284 requires, “damages” includes lost profits on competing products not covered by the infringed claims.
III. Application of the “But For” Standard
To recover lost profits damages for patent infringement, the patent owner must show that it would have received the additional profits “but for” the infringement. The patent owner bears the burden to present evidence sufficient to show a reasonable probability that it would have made the asserted profits absent infringement. See, e.g., Del Mar Avionics, Inc. v. Quinton Instr. Co., 836 F.2d 1320, 1326, 5 USPQ2d 1255, 1260 (Fed.Cir.1987). This court has prescribed no one particular method by which the patent owner must meet this burden; “the methodology of assessing and computing damages is committed to the sound discretion of the district court.” State Indus., Inc. v. Mor-Flo Indus., Inc., 883 F.2d 1573, 1576-77, 12 USPQ2d 1026, 1028 (Fed.Cir.1989), cert. denied, 493 U.S. 1022, 110 S.Ct. 725, 107 L.Ed.2d 744 (1990).
To prevail in its appeal of the amount of damages imposed, Tapematic must show that the district court committed an abuse of discretion, basing the award on clearly erroneous factual findings, legal error, or a manifest error of judgment. State Industries, 883 F.2d at 1577.
[953]*953In determining the amount of damages to which King was entitled, the district court considered:
(1) the number of lost sales; (2) the gross receipts King would have obtained from the lost sales had there been no infringement by Tapematic; (3) the cost of sales to be deducted from gross receipts; and (4) King’s profit on the lost sales.
King, 737 F.Supp. at 1241.
The district court determined that King-controlled 70% of the tapeloader market pri- or to Tapematic’s infringement. The district court also found that Tapematic sold 77 infringing machines (Tapematic Model 2,002). Id. The district court determined that, absent Tapematic’s infringing Model 2,002, buyers would have purchased replacements according to the other sellers’ market share. Because King controlled 70% of the market, the district court initially determined that King could have made 70% of those replacement sales. Id. at 1242.
The district court then took into account the differences between the Tapematic Model 2,002 and the King Model 790. The Tape-matic 2,002 is a double, not a single, pancake loader. Therefore, Tapematic argued that its customers would not have bought a single pancake loader like the King Model 790. Giving some weight to this argument, the district court reduced the number of King’s lost sales. The district court also awarded King lost profits on the spare parts for the machines it would have sold but for Tapematic’s infringement. Id.
The district court also found that the machines which, but for Tapematic’s sales, would have been sold by companies other than King were acceptable noninfringing alternatives. The district court determined that King was entitled to a reasonable royalty based on Tapematie’s sales price and the number of these machines. Finally, the district court gave King prejudgment interest at the rate of 11%.
This court finds no clear error or abuse of discretion in the district court’s careful analysis. Accordingly, this court affirms the district court’s damages assessment. See State Industries, 883 F.2d at 1577.
CONCLUSION
Because it detects no clear error, this court affirms the district court’s finding of infringement of the ’461 patent. Similarly, this court detects no clear error and affirms the district court’s findings that Tapematic has not infringed either the 153 or the 123 patent. Finally, this court detects no clear error or abuse of discretion and affirms the district court’s damages assessment.
COSTS
Each party shall bear its own costs for this appeal.
AFFIRMED