Opinion of the court filed by Circuit Judge LOURIE. Dissenting opinion filed by Chief Judge MAYER.
LOURIE, Circuit Judge.
Atmel Corporation appeals from the decision of the United States District Court for the Northern District of California granting summary judgment to Informa[1376]*1376tion Storage Devices, Inc. (“ISD”) that claim 1 of Atmel’s patent, U.S. Patent 4,511,811, is invalid for indefiniteness. See Atmel Corp. v. Information Storage Devices, Inc., No. C-95-1987-FMS, 1998 WL 184274 (N.D.Cal. Apr.14, 1998). Because the district court erred by failing to consider the knowledge of one skilled in the art that indicated that the specification disclosed sufficient structure to satisfy 35 U.S.C. § 112, ¶ 2, we reverse and remand.
BACKGROUND
The ’811 patent pertains to an improved “charge pump” circuit which is able to boost the voltage applied to, for example, a word line in a memory array during a programming operation without excessive current leakage. Claim 1, the sole claim of the patent, reads as follows:
1. An apparatus for selectively increasing the voltage on one or more of a plurality of conductive lines having inherent distributed capacitance disposed in a semiconductor circuit comprising:
means disposed on said semiconductor circuit for selecting one or more of said conductive lines;
high voltage generating means disposed on said semiconductor circuit for generating a high voltage from a lower voltage power supply connected to said semiconductor circuit;
voltage pulse generating means disposed on said semiconductor circuit for generating voltage pulses;
means for capacitively coupling voltage pulses from said voltage pulse generating means to a voltage node in said semiconductor circuit;
transfer means responsive to said selecting means and connected to said voltage node for transferring increments of charge from said high voltage generating means to the inherent distributed capacitance in selected ones of said conductive lines in response to said voltage pulses;
said transfer means including switching means cooperating with said selecting means for blocking substantially all of the flow of current through and transfer of charge from said high voltage generating means to said conductive lines which are unselected.
’811 patent, col. 8,ll. 17-45 (emphasis added).
In June 1995, Atmel filed a complaint in the district court alleging that ISD was liable for infringement of claim 1. See Atmel Corp. v. Information Storage Devices, Inc., 997 F.Supp. 1210, 1214 (N.D.Cal.1998). In November 1997, ISD moved for summary judgment that, inter alia, claim 1 was indefinite under § 112, ¶ 2,1 alleging that the specification failed to disclose any structure corresponding to the disputed high-voltage means limitation. See id. ISD further requested that the district court simultaneously consider its motion along with the court’s claim construction. See id. After ruling that it would be more efficient to construe the claims before ruling on validity, see id., the court proceeded to construe claim 1.
The district court first held, as a matter of law, that the disputed limitation is expressed in means-plus-function format under 35 U.S.C. § 112, ¶ 6.2 See id. at 1227. Neither party appeals this ruling. The [1377]*1377court then observed that the portion of the specification that pertains to the structural component of this means-plus-function limitation discloses that:
[Tjhe present invention may include high-voltage generator circuit 34. Known Circuit techniques are used to implement high-voltage circuit 34. See On-Chip High Voltage Generation in NMOS Integrated Circuits Using an Improved Voltage Multiplier Technique, IEEE Journal of Solid State Circuits, Vol[.] SC-11, No. 3, June 1976 [the “Dickson article”].
’811 patent, col. 4, 11. 56-63. The district court also noted that Figures 2 and 4 of the ’811 patent only depict the high-voltage generator circuit as a “black box,” see At-mel, 997 F.Supp. at 1227, ie., they provide no detail as to what electrical components, e.g., transistors, resistors, or capacitors, comprise that circuit.3 The district court then held that, based on the language in the written description set forth above, “the structure corresponding to the high voltage generating means cannot be any circuits beyond those described in the Dickson article.” Id. For the district court, the resolution of the case turned on the permissibility of incorporating structures corresponding to the high-voltage means limitation by reference to material not in the specification. The court requested further briefing on this issue prior to ruling on ISD’s motion for summary judgment. See id. at 1230.
After receiving this briefing, the court adopted the rule set forth in the version of the Manual of Patent Examining Procedure (MPEP), § 608.01(p), in effect at the time the patent application was filed.4 See Atmel, 1998 WL 184274, at *2-*3. In relevant part, that section states that material “necessary to ... support the claims” may not be incorporated by reference to a nonpatent publication. MPEP § 608.01(p) (4th ed., Rev.8, 1981). Interpreting such “essential material” to include the structure corresponding to a means-plus-function limitation, the court concluded that the ’811 patent improperly incorporated structure corresponding to the high-voltage means limitation by reference to the Dickson article; accordingly, the district court disregarded the structures disclosed in that publication. See Atmel, 1998 WL, 184274, at *3. In view of its prior holding that the structures corresponding to the high-voltage means limitation were limited by the specification itself to those set forth in the Dickson article, see Atmel, 997 F.Supp. at 1227, the court held that the resulting absence of any structure in the specification corresponding to the disputed limitation rendered the claim invalid as indefinite under 35 U.S.C. § 112, ¶ 2. See Atmel, 1998 WL 184274, at *3 (citing In re Dossel, 115 F.3d 942, 946, 42 USPQ2d 1881, 1884-85 (Fed.Cir.1997)).
The district court then rejected ISD’s argument that it should determine whether the claim was indefinite based on the way the disclosure would be understood by one skilled in the art, not on the “technical form” of the specification. See Atmel, 1998 WL 184274, at *3. In disregarding Atmel’s expert testimony in support of its argument, the court concluded that:
[1378]*1378Section 112, ¶ 6 ... requires that the specification disclose a structure corresponding to the claimed means.
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Opinion of the court filed by Circuit Judge LOURIE. Dissenting opinion filed by Chief Judge MAYER.
LOURIE, Circuit Judge.
Atmel Corporation appeals from the decision of the United States District Court for the Northern District of California granting summary judgment to Informa[1376]*1376tion Storage Devices, Inc. (“ISD”) that claim 1 of Atmel’s patent, U.S. Patent 4,511,811, is invalid for indefiniteness. See Atmel Corp. v. Information Storage Devices, Inc., No. C-95-1987-FMS, 1998 WL 184274 (N.D.Cal. Apr.14, 1998). Because the district court erred by failing to consider the knowledge of one skilled in the art that indicated that the specification disclosed sufficient structure to satisfy 35 U.S.C. § 112, ¶ 2, we reverse and remand.
BACKGROUND
The ’811 patent pertains to an improved “charge pump” circuit which is able to boost the voltage applied to, for example, a word line in a memory array during a programming operation without excessive current leakage. Claim 1, the sole claim of the patent, reads as follows:
1. An apparatus for selectively increasing the voltage on one or more of a plurality of conductive lines having inherent distributed capacitance disposed in a semiconductor circuit comprising:
means disposed on said semiconductor circuit for selecting one or more of said conductive lines;
high voltage generating means disposed on said semiconductor circuit for generating a high voltage from a lower voltage power supply connected to said semiconductor circuit;
voltage pulse generating means disposed on said semiconductor circuit for generating voltage pulses;
means for capacitively coupling voltage pulses from said voltage pulse generating means to a voltage node in said semiconductor circuit;
transfer means responsive to said selecting means and connected to said voltage node for transferring increments of charge from said high voltage generating means to the inherent distributed capacitance in selected ones of said conductive lines in response to said voltage pulses;
said transfer means including switching means cooperating with said selecting means for blocking substantially all of the flow of current through and transfer of charge from said high voltage generating means to said conductive lines which are unselected.
’811 patent, col. 8,ll. 17-45 (emphasis added).
In June 1995, Atmel filed a complaint in the district court alleging that ISD was liable for infringement of claim 1. See Atmel Corp. v. Information Storage Devices, Inc., 997 F.Supp. 1210, 1214 (N.D.Cal.1998). In November 1997, ISD moved for summary judgment that, inter alia, claim 1 was indefinite under § 112, ¶ 2,1 alleging that the specification failed to disclose any structure corresponding to the disputed high-voltage means limitation. See id. ISD further requested that the district court simultaneously consider its motion along with the court’s claim construction. See id. After ruling that it would be more efficient to construe the claims before ruling on validity, see id., the court proceeded to construe claim 1.
The district court first held, as a matter of law, that the disputed limitation is expressed in means-plus-function format under 35 U.S.C. § 112, ¶ 6.2 See id. at 1227. Neither party appeals this ruling. The [1377]*1377court then observed that the portion of the specification that pertains to the structural component of this means-plus-function limitation discloses that:
[Tjhe present invention may include high-voltage generator circuit 34. Known Circuit techniques are used to implement high-voltage circuit 34. See On-Chip High Voltage Generation in NMOS Integrated Circuits Using an Improved Voltage Multiplier Technique, IEEE Journal of Solid State Circuits, Vol[.] SC-11, No. 3, June 1976 [the “Dickson article”].
’811 patent, col. 4, 11. 56-63. The district court also noted that Figures 2 and 4 of the ’811 patent only depict the high-voltage generator circuit as a “black box,” see At-mel, 997 F.Supp. at 1227, ie., they provide no detail as to what electrical components, e.g., transistors, resistors, or capacitors, comprise that circuit.3 The district court then held that, based on the language in the written description set forth above, “the structure corresponding to the high voltage generating means cannot be any circuits beyond those described in the Dickson article.” Id. For the district court, the resolution of the case turned on the permissibility of incorporating structures corresponding to the high-voltage means limitation by reference to material not in the specification. The court requested further briefing on this issue prior to ruling on ISD’s motion for summary judgment. See id. at 1230.
After receiving this briefing, the court adopted the rule set forth in the version of the Manual of Patent Examining Procedure (MPEP), § 608.01(p), in effect at the time the patent application was filed.4 See Atmel, 1998 WL 184274, at *2-*3. In relevant part, that section states that material “necessary to ... support the claims” may not be incorporated by reference to a nonpatent publication. MPEP § 608.01(p) (4th ed., Rev.8, 1981). Interpreting such “essential material” to include the structure corresponding to a means-plus-function limitation, the court concluded that the ’811 patent improperly incorporated structure corresponding to the high-voltage means limitation by reference to the Dickson article; accordingly, the district court disregarded the structures disclosed in that publication. See Atmel, 1998 WL, 184274, at *3. In view of its prior holding that the structures corresponding to the high-voltage means limitation were limited by the specification itself to those set forth in the Dickson article, see Atmel, 997 F.Supp. at 1227, the court held that the resulting absence of any structure in the specification corresponding to the disputed limitation rendered the claim invalid as indefinite under 35 U.S.C. § 112, ¶ 2. See Atmel, 1998 WL 184274, at *3 (citing In re Dossel, 115 F.3d 942, 946, 42 USPQ2d 1881, 1884-85 (Fed.Cir.1997)).
The district court then rejected ISD’s argument that it should determine whether the claim was indefinite based on the way the disclosure would be understood by one skilled in the art, not on the “technical form” of the specification. See Atmel, 1998 WL 184274, at *3. In disregarding Atmel’s expert testimony in support of its argument, the court concluded that:
[1378]*1378Section 112, ¶ 6 ... requires that the specification disclose a structure corresponding to the claimed means. A patent holder cannot evade that requirement with a conclusory assertion that one skilled in the art would understand the claimed means despite the failure to disclose a structure. Under In re Dos-sel, the failure to comply with section 112, ¶ 6 necessarily violates section 112, ¶ 2.
Id. at *4.
Atmel appealed the district court’s grant of summary judgment of indefiniteness to this court. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1) (1994).
DISCUSSION
A. Standards of Review
Summary judgment is appropriate when there are no genuine issues of material fact and the moving party is entitled to judgment as a matter of law. Fed. R.Civ.P. 56(c). We review a district court’s grant of summary judgment de novo, reapplying the summary judgment standard. See Conroy v. Reebok Int’l, Ltd., 14 F.3d 1570, 1575, 29 USPQ2d 1373, 1377 (Fed.Cir.1994).
“A determination of claim indefiniteness is a legal conclusion that is drawn from the court’s performance of its duty as the construer of patent claims.” See Personalized Media Communications, LLC v. International Trade Comm’n, 161 F.3d 696, 705, 48 USPQ2d 1880, 1888 (Fed.Cir.1998). Indefiniteness, therefore, like claim construction, is a question of law that we review de novo. See id. at 702, 161 F.3d 696, 48 USPQ2d at 1886; cf. Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1456, 46 USPQ2d 1169, 1174 (Fed.Cir.1998) (en banc) (holding that claim construction is a question of law reviewed de novo).
B. The Understanding of One Skilled in the Art
Citing In re Dossel, Atmel argues that the district court erred in not determining whether the high-voltage means limitation is sufficiently definite under § 112, ¶ 2 based on the way one skilled in the art would understand that limitation in view of the specification. See In re Dossel, 115 F.3d 942, 42 USPQ2d 1881 (Fed.Cir.1997). ISD responds that the knowledge available to such a person cannot serve as a substitute for adequate disclosure of structure in the specification. We also understand ISD to argue that even if the court failed to apply the proper standard, that error is harmless in view of its assertion of a total absence of structure in the specification corresponding to the high-voltage means limitation.
We agree with Atmel that the district court erred in its analysis under § 112, ¶ 2 and should have determined whether sufficient structure was disclosed in the specification based on the understanding of one skilled in the art. As a general matter, it is well-established that the determination whether a claim is invalid as indefinite “depends on whether those skilled in the art would understand the scope of the claim when the claim is read in light of the specification.” North Am. Vaccine, Inc. v. American Cyanamid Co., 7 F.3d 1571, 1579, 28 USPQ2d 1333, 1339 (Fed.Cir.1993); see Miles Lab., Inc. v. Shandon, Inc., 997 F.2d 870, 875, 27 USPQ2d 1123, 1126 (Fed.Cir.1993). For purposes of § 112 ¶ 2, it is the disclosure in the specification itself, not the technical form of the disclosure that counts. In In re Donaldson Co., Inc., we explained how § 112, ¶ 2 applies in the specific context of a § 112, ¶ 6 means-plus-function claim limitation:
Although [§ 112, ¶ 6] statutorily provides that one may use means-plus-function language in a claim, one is still subject to the requirement that a claim “particularly point out and distinctly claim” the invention [§ 112, ¶ 2], Therefore, if one employs means-plus-function language in a claim, one must set forth in the specification an adequate disclo[1379]*1379sure showing what is meant by the claim language. If an applicant fails to set forth an adequate disclosure, the applicant has in effect failed to particularly point out and distinctly claim the invention as required by the second paragraph of section 112.
Donaldson, 16 F.3d 1189, 1195, 29 USPQ2d 1845, 1850 (Fed.Cir.1994). In In re Dossel we implied that the “one skilled in the art” mode of analysis applies with equal force when determining whether a § 112, ¶ 6 means-plus-function limitation is sufficiently definite under § 112, ¶ 2. In Dossel, the parties disputed whether adequate structure (in that case, a computer) was disclosed to support the “reconstructing means” limitation in the claims at issue. See Dossel, 115 F.3d at 946-47, 42 USPQ2d at 1885. In concluding that the claim limitation was sufficiently definite under § 112, ¶ 2, the understanding of one skilled in the art was an integral part of our analysis:
Clearly, a unit which receives digital data, performs complex mathematical computations and outputs the results to a display must be implemented by or on a general or special purpose computer (although it is not clear why the written description does not simply state “computer” or some equivalent phrase). To bolster this result, we note that, in the medical imaging field, it is well within the realm of common experience that computers are used to generate images for display by mathematically processing digital input.
See id. at 947, 42 USPQ2d at 1885 (emphasis added).
That the “one skilled in the art” analysis should apply in determining whether sufficient structure has been disclosed to support a means-plus-function limitation flows naturally from the relationship between claim construction and § 112, ¶ 2. We have previously observed that an analysis under § 112, ¶ 2 is inextricably intertwined with claim construction, see Personalized Media, 161 F.3d at 705, 48 USPQ2d at 1888, and that in the § 112, ¶ 6 context, a court’s determination of the structure that corresponds to a particular means-plus function limitation is indeed a matter of claim construction, see Chiuminatta Concrete Concepts, Inc. v. Cardinal Indus., Inc., 145 F.3d 1303, 1308, 46 USPQ2d 1752, 1756 (Fed.Cir.1998). As it is well-established that claims are to be construed in view of the understanding of one skilled in the art, see, e.g., K-2 Corp. v. Salomon S.A., 191 F.3d 1356, 1365, 52 USPQ2d 1001, 1006 (Fed.Cir.1999) (noting that “claim construction is firmly anchored in reality by the understanding of those of ordinary skill in the art”), the closely related issue concerning whether sufficient structure has in fact been disclosed to support a means-plus-function limitation should be analyzed under the same standard.
Moreover, the “one skilled in the art” analysis in this context is in accord with related analyses under § 112, ¶ l,5 viz., enablement, see § 112, ¶ 1 (providing that the enablement requirement is satisfied if the patent applicant sets forth in the written description what one skilled in the art would need to know to make and use the claimed invention); best mode, see Chemcast Corp. v. Arco Indus. Corp., 913 F.2d 923, 927, 16 USPQ2d 1033, 1036 (Fed.Cir.1990) (“[W]hether a best mode disclosure is adequate, that is, whether the inventor concealed a better mode of practicing his invention than he disclosed, is a function not only of what the inventor knew but also how one skilled in the art would have understood his disclosure.”); and written description, see Vas-Cath, Inc. v. Mahur-[1380]*1380kar, 935 F.2d 1555, 1563-64, 19 USPQ2d 1111, 1117 (Fed.Cir.1991) (holding that, to satisfy the written description requirement, “the applicant must ... convey with reasonable clarity to those skilled in the art that ... he or she was in possession of the invention.”). For the reasons outlined above, we thus conclude that the district court erred by failing to assess whether sufficient structure was disclosed in the specification to support the high-voltage means limitation based on the understanding of one skilled in the art.
We are aware that the PTO has recently issued proposed Supplemental Examiner Guidelines that adopt our reasoning in Dossel with respect to determining whether adequate structure has been disclosed to support a means-plus-function limitation. The proposed supplemental guidelines state in relevant part that:
The written description does not have to explicitly describe the structure (or material or acts) corresponding to a means(or step-) plus-function limitation to particularly point out and distinctly claim the invention as required by 35 U.S.C. 112 ¶ 2. Rather, disclosure of structure corresponding to a means-plus-function limitation may be implicit in the written description if it would have been clear to those skilled in the art what structure must perform the function recited in the means-plus-function limitation.
PTO Supplemental Examiner Guidelines on Applying 35 U.S.C. § 112 ¶ 6, 58 Fed. Reg. 443, 444 & nn. 12 & 13 (1999) (emphasis added) (footnotes omitted). These guidelines would thus seem to be consistent with our holding on this point.
ISD asserts that consideration of the understanding of one skilled in the art in no way relieves the patentee of adequately disclosing sufficient structure in the specification. We agree. As we stated in Donaldson, “[I]f one employs means-plus-function language in a claim, one must set forth in the specification an adequate disclosure showing what is meant by the claim language.” Donaldson, 16 F.3d at 1195, 29 USPQ2d at 1850 (emphasis added); see Dossel, 115 F.3d at 946, 42 USPQ2d at 1884 (“Failure to describe adequately the necessary structure, material, or acts [corresponding to a means-plus-function limitation] in the written description means that the drafter has failed to comply with § 112, ¶ 2.”); B. Braun Med., Inc. v. Abbott Lab., 124 F.3d 1419, 1424, 43 USPQ2d 1896, 1900 (Fed.Cir.1997) (holding that the “structure disclosed in the specification is ‘corresponding’ structure only if the specification or prosecution history links or associates that structure to the function recited in the claim”). However, interpretation of what is disclosed must be made in light of the knowledge of one skilled in the art. Having settled the proper standard under which a court must assess the adequacy of disclosure of structure corresponding to a means-plus-function limitation, we now turn to the disclosure of the ’811 patent.
C. Sufficiency of the Disclosure
Atmel argues that the district court erred in adopting the relevant version of MPEP § 608.01(p), which prohibits the incorporation of “essential material” by reference to nonpatent publications. Accordingly, Atmel contends that the court also erred in holding that the structures described in the Dickson article could not be incorporated by reference into the ’811 patent. Atmel asserts that the rule articulated by the district court not only conflicts with our precedent, but would encourage patentees to include inordinate quantities of written material in the specification for fear of omitting “essential material.” Alternatively, Atmel contends that sufficient structure is provided in the specification even if one does not refer to the contents of the Dickson article. Atmel specifically directs us to the testimony of its expert, Michael Callahan, that the mere mention of the title of the Dickson article in the specification is sufficient for one skilled in [1381]*1381the art to envision the structures disclosed in that article.
ISD responds that the district court correctly followed MPEP § 608.01(p) and properly excluded the structures described in the Dickson article. ISD argues that based on the plain language of § 112, ¶ 6, incorporation by reference cannot be substituted for a disclosure in the specification. See 35 U.S.C. § 112, ¶6 (1994). ISD asserts that incorporation by reference contravenes the public notice function that patents and their prosecution histories provide with respect to understanding the extent of a patentee’s right to exclude, because competitors are unable to determine claim scope without burdensome reference to extrinsic evidence. ISD also responds that the district court properly limited the possible structures corresponding to the high-voltage means limitation to those in the Dickson article, and since the district court correctly excluded the contents of that article, the court properly held that no structure was disclosed corresponding to the high-voltage means limitation, thus rendering the claim indefinite.
We agree with ISD that the district court correctly held that structure supporting a means-plus-function claim under § 112, ¶ 6 must appear in the specification. We disagree with the district court, however, that an inquiry under § 112 ¶ 2 turns on whether a patentee has “incorporated by reference” material into the specification relating to structure. Instead, the inquiry asks first whether structure is described in specification, and, if so, whether one skilled in the art would identify the structure from that description. As we discuss below, we believe that these requirements of § 112 are revealed by its language and purpose, and we consider the issue in the context of the disclosure requirements of the statute rather than utilize the concept of incorporation by reference.
For the sake of clarity, we first set out in one place the provisions of § 112, ¶¶ 1, 2, and 6.
§ 112. Specification
[¶ 1] The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
[¶ 2] The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
[¶ 6] An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
35 U.S.C. § 112, ¶¶ 1, 2, and 6 (1994).
Paragraph 1 is, inter alia, an enablement provision requiring that an inventor set forth in the patent specification how to make and use his or her invention. Paragraph 2 requires claims that particularly and distinctly indicate the subject matter that the inventor considers to be his or her invention. Paragraph 6 also addresses claim language, but refers to the specification for its meaning. In doing so, it specifically refers to “structure ... described in the specification and equivalents thereof.” Id. § 112, ¶ 6. This provision represents a quid pro quo by permitting inventors to use a generic means expression for a claim limitation provided that the specification indicates what structure(s) constitute(s) the means. See O.I. Corp. v. Tekmar Co., 115 F.3d 1576, 1583, 42 USPQ2d 1777, 1782 (Fed.Cir.1997). The language indicates that means-plus-function clauses comprise not only the language of the claims, but also the structure [1382]*1382corresponding to that means that is disclosed in the written description portion of the specification (and equivalents thereof). Thus, in order for a claim to meet the particularity requirement of ¶ 2, the corresponding structure(s) of a means-plus-function limitation must be disclosed in the written description in such a manner that one skilled in the art will know and understand what structure corresponds to the means limitation. Otherwise, one does not know what the claim means.
Fulfillment of the § 112, ¶ 6 tradeoff cannot be satisfied when there is a total omission of structure. There must be structure in the specification. This conclusion is not inconsistent with the fact that the knowledge of one skilled in the particular art may be used to understand what structure(s) the specification discloses, or that even a dictionary or other documentary source may be resorted to for such assistance, because such resources may only be employed in relation to structure that is disclosed in the specification. Paragraph 6 does not contemplate the kind of open-ended reference to extrinsic works that ¶ 1, the enablement provision, does.
Paragraph 1 permits resort to material outside of the specification in order to satisfy the enablement portion of the statute because it makes no sense to encumber the specification of a patent with all the knowledge of the past concerning how to make and use the claimed invention. One skilled in the art knows how to make and use a bolt, a wheel, a gear, a transistor, or a known chemical starting material. The specification would be of enormous and unnecessary length if one had to literally reinvent and describe the wheel.
Section 112, ¶ 6, however, does not have the expansive purpose of ¶ 1. It sets forth a simple requirement, a quid pro quo, in order to utilize a generic means expression. All one needs to do in order to obtain the benefit of that claiming device is to recite some structure corresponding to the means in the specification, as the statute states, so that one can readily ascertain what the claim means and comply with the particularity requirement of ¶ 2. The requirement of specific structure in § 112, ¶ 6 thus does not raise the specter of an unending disclosure of what everyone in the field knows that such a requirement in § 112, ¶ 1 would entail. If our interpretation of the statute results in a slight amount of additional written description appearing in patent specifications compared with total omission of structure, that is the trade-off necessitated by an applicant’s use of the statute’s permissive generic means term.
Atmel argues that even though the text of the Dickson article is not in the specification, sufficient structure is nevertheless disclosed in the specification, and that the district court erred in limiting possible structures corresponding to the high-voltage generating means to those structures included in the Dickson article. While we do agree with ISD that the district court properly held that the Dickson article may not take the place of structure that does not appear in the specification, the specification plainly states that “[k]nown Circuit techniques are used to implement high-voltage circuit 34. See On-Chip High Voltage Generation in NMOS Integrated Circuits Using an Improved Voltage Multiplier Technique, IEEE Journal of Solid State Circuits .... ” ’811 patent, col. 4,11. 58-62. Atmel’s expert, Callahan, testified that this title alone was sufficient to indicate to one skilled in the art the precise structure of the means recited in the specification. The record indicates that that testimony was essentially unrebutted. That being the case, we conclude that summary judgment was improperly granted invalidating the ’811 patent for indefiniteness under § 112, ¶ 2. We therefore reverse the grant of summary judgment of invalidity and remand for further consideration of other issues consistent with this opinion.
[1383]*1383CONCLUSION
The district court properly concluded that the statutory requirement of disclosure of structure corresponding to the high-voltage means limitation can only be met by reference to those structures disclosed in the specification. However, the district court erred by failing to consider the knowledge of one skilled in the art that indicated, based on unrefuted testimony, that the specification disclosed sufficient structure corresponding to the high-voltage means limitation.
Accordingly, we
REVERSE and REMAND.