Full opinion text
MEMORANDUM OPINION AND ORDER BRYAN, District Judge. This is a patent infringement action. The plaintiff, Lundy Electronics & Systems, Inc. (Lundy), a New York corporation with its principal office and place of business at Glen Head, New York, has asserted that the defendant, Optical Recognition Systems, Inc. (ORS), a Delaware corporation with its principal office and place of business at Reston, Virginia, is infringing U. S. Patent No. 3,535,682 (the Patent or Dykaar) by manufacturing, using and selling machines embodying the claimed subject matter of the Patent. Lundy is the assignee and owner of all interest in that patent. ORS has denied that it infringes the Patent and has counterclaimed for a judgment declaring the Patent invalid, not infringed and unenforceable. Jurisdiction is founded upon 28 U.S.C. §§ 1338(a), 2201 and 2202. Venue is founded upon 28 U.S.C. § 1400(b). The trial began on December 4, 1972 where the issues of the litigation were limited to claims 1-4, 9, 11-16, 23, 24, 28 and 30. Following the trial the plaintiff was allowed to take further de bene esse depositions of certain witnesses whose de bene esse depositions had been offered at trial by the defendant. Those were concluded on February 5, 1973, and post-trial briefs were filed on February 26, 1973. Lundy has for some years produced and sold a reader for magnetic ink character recognition (MICR). This device “reads” the characters which we all now find imprinted on the lower edge of our checks and deposit slips. Oversimplified, the characters are imprinted on the checks with ink containing a magnetizable substance. These characters are specifically designed so that when they pass under a magnetic charging head and a transducer, from left to right (contrary to the embodiment, Fig. 2, of the Patent which shows passage from right to left), an analog waveform is generated. There are fourteen possible characters comprising what is known as the E-13B font. Ideally each character when read produces a distinctive analog waveform. The distinctive waveform generated by the character “O” is shown in Fig. 2 of the embodiment of the Patent. P.Ex. 14. It and the others are shown in P.Ex. 15A, attached as Appendix I. This analog electrical signal is converted, through a complex electronic circuitry, to digital signals representative of information peculiar to the character read. Because of extraneous influences as well as such -imperfections in the printing as uneven density of ink and skew of characters, the “ideal” is rarely met. For that reason a reconstruction of the character must be attempted from those portions of the character which are typical of the ideal. The aim of Lundy and the accused device is to accomplish this. Character recognition is accomplished by comparing the amplitudes of portions of a character’s waveform to a previous or other portion of the waveform. Information bearing digital signals resulting from and representative of these comparisons are generated. They can then be utilized to generate signals identifying the waveforms (characters) in question. P.Ex. 14; Schwarz Tr. 121-129. ORS has in the past manufactured and sold machines for the reading of detectable characters on documents such as checks. Its system, however, reads the characters optically rather than by MICR. As an adjunct of its optical reader it developed a MICR reader which is the accused device in this action. For reasons that are later stated, the Court concludes that the Patent is valid, but that in light of the prior art, particularly the Perotto patent (Perot-to) (D.Ex. 1), what the inventors have done “works only a slight step forward.” Consequently their patent should be given a “narrow scope” resulting in no infringement unless the machine of ORS is an “approximate copy” of the Lundy patent. Under that view there is no infringement here. Eibel Co. v. Paper Co., 261 U.S. 45, 63, 43 S.Ct. 322, 67 L.Ed. 523 (1923); Hazeltine Research, Inc. v. Firestone Tire and Rubber Co., 468 F.2d 1277 (4th Cir. 1972). If the Lundy patent is a significant enough improvement over Perotto to sustain the Lundy patent against an attack on the ground that it was anticipated by Perotto, then the device of ORS is significantly enough different from Lundy to withstand any charge by the latter of infringement. The principal in Perotto, Lundy and ORS of recognizing a waveform by comparison of one or more samplings thereof with another sampling or portion is basically the same. However, the method by which this is accomplished and the degree of accuracy resulting therefrom are what distinguish the three. In the Court’s view, Lundy ought not to be allowed to stand pat with its device and stifle further improvements by invoking a broad interpretation of the claims of its patent. THE PLAINTIFF AND THE PATENT IN SUIT Until 1963, Lundy’s business consisted principally of electronic defense systems unrelated to the subject matter of this litigation. In October 1963, one David E. Dykaar proposed that a magnetic ink character recognition (MICR) system for use in a bank check sorter might be a possible area of diversification for Lundy, and work was- begun on this project in December 1963. A preproduction machine was shown to the industry in early 1965 with the hope that a compact, relatively inexpensive reader would meet a demand as yet unfilled by the large, expensive, high-speed readers then available. Barbato Tr. 42. This machine was well received and interest was expressed by International Business Machine Corporation (IBM) and National Cash Register Company (NCR). A patent application was filed on June 1, 1965, based on this preproduction machine including the MICR reader and various electro-mechanical features of the document handling and sorting apparatus. This resulted in U. S. Patent No. 3,363,756. P.Ex. 15. IBM and Lundy jointly conducted tests on the preproduction machine and it was determined that when nonuniform characters of the E-13B font (such as may be expected to be encountered in actual commercial applications) were used, the performance of the machine was unsatisfactory by IBM standards. Accordingly work was begun by Lundy on the development of an improved reader in March or April of 1965. A preproduction or breadboard system was first tested in August and September of 1965' and was found to perform better than' the previous device and to satisfy the commercial standards of IBM. The patent application culminating in the Patent was filed on this system on December 10, 1965. Barbato Tr. 7 — 19, 42, P. Ex. 1. PROSECUTION HISTORY The history of the Patent indicates, that the application as filed contained twenty-six claims plus one “omnibus” claim 27 included for the purposes of possibly filing corresponding foreign applications. P.Ex. 13. Of the first twenty-six claims, claims 1, 5 and 9 were independent method claims and claims 10, 11, 16, 22, 25 and 26 were independent apparatus claims. The remaining seventeen claims were drafted in dependent form. On December 13, 1967, a voluntary preliminary amendment was filed by Lundy’s attorneys prior to any official action by the Patent Office on the merits of the application. All of the claims were revised and amended by the insertion or deletion of certain claim language. The omnibus claim 27 was can-celled and four new dependent claims, 28-31, were added. In the remarks accompanying the preliminary amendment it was suggested to the Examiner that he consider the seven United States patents and four foreign patents listed. P. Ex. 13, pp. 29-36. Of the seven United States patents listed, four were classified officially by the Patent Office in class 340, subclass 146.3, the same subclass in which the Examiner indicated he conducted his search and in which the Patent is now classified. D.Ex. 11. A search was conducted by the Examiner in subclass 340-146.3 on October 21, 1968. P.Ex. 13 (last page, search notes). In the first Official Action by the Patent Office, dated -December 9, 1968, the Examiner acknowledged receipt of the preliminary amendment. P.Ex. 13, pp. 39-44. In addition, three claims were allowed and six other claims were indicated as being allowable if amended to further specify how the reference voltage level was a function of the analog signal and how identification is made. The remaining claims were rejected by the Examiner as unpatentable over four new references not listed in the acknowledged preliminary amendment, the principal two of which were classified in subclass 340-146.3. In a response to the first Official Action filed March 10, 1969, all of the claims (except for the three previously allowed claims) were amended and a detailed discussion was presented by Lundy’s attorneys as to how the previously rejected (but now amended) claims were distinguished from the four references cited by the Examiner. P.Ex. 13, pp. 45-69. In a second Official Action dated May 14, 1969, the Examiner allowed ten more claims (Patent claims 9, 10, 12-17, 28 and 29). P.Ex. 13, pp. 70-72. In addition, twelve claims were rejected under 35 U.S.C. § 112 as being vague and indefinite for specific reasons and nine claims were rejected as being obvious over a newly cited reference (a patent to Bartz officially classified as a cross-reference in class 340-146.3) in view of one of the references from class 340-146.3 cited in the first Official Action. On August 13, 1969, a response was filed to the second Official Action further amending what became Patent claims 18 and 21, cancelling two claims and adding four independent method and apparatus claims (later cancelled). P. Ex. 13, pp. 73-83. A detailed discussion was included regarding the various rejections, the newly cited references and the previously cited art. On October 16, 1969, the Patent Office issued a third Official Action continuing the same grounds for rejection as in the second Official Action and making a new rejection of one of the newly added claims. P.Ex. 13, pp. 84-86. This action was made final in accordance with established Patent Office practice. On February 16, 1970, an amendment after final rejection was filed adding, as requested by the Examiner, Figure 3A and an appropriate description in the specification as to the exemplary circuit details of the signal generator 60. P. Ex. 13, pp. 89-99. Additional amendments were made to five of the independent claims (which became Patent claims 1, 6, 11, 18 and 26), five claims were cancelled and a new claim was added which became Patent claim 30. Following a telephone interview initiated by the Examiner to one of the Lundy attorneys, Granville M. Brumbaugh, Jr., on February 27, 1970, and made of record by the Examiner in the prosecution history of the Patent, the application was allowed. Stipulation; P.Ex. 13, p. 102. In accordance with this telephone interview an Examiner’s Amendment was entered on April 10, 1970, setting forth amendments to what became Patent claims 1, 6 and 30. P.Ex. 13, p. 105. DYKAAR-LUNDY READER The Lundy reader is a method and apparatus for recognizing highly stylized magnetic ink characters (e.g., the E-13B font) by exposing them, by means of mechanical roller apparatus, first to a magnetic charging head which installs magnetic characteristics to the ink in those characters and secondly by exposing them to a transducer or magnetic reading head, the exposure being carefully regulated. Each of the fourteen characters of the E-13B font generates a distinctive analog electrical signal or waveform by the response of the transducer to the magnetic characteristics of the character being read. P.Ex. 15A, Appendix I. The analog electrical signal generated from the reading head is amplified and fed into a “lead edge trigger circuit,” whose function is to detect the input of the waveform, i.e., the arrival of a character at the transducer. When the “beginning” of the analog electrical signal is detected, the “lead edge trigger circuit” activates various timing components which permit sampling of the analog waveform at selected times as the individual character passes under the transducer. The amplitudes of the sampled portions of the developing electrical signal are compared to at least one reference voltage level which is “effective” during the generation of the timing pulses (the sampling procedure) and which is directly related to a predetermined portion of the waveform. The “lead edge trigger circuit” also activates other components which enable the reader not only to detect by means of a peak detector but store the amplitude of the first positive pluse at time Ti, thereby establishing from that positive pulse a reference voltage level (about which more will be said later). The output of the peak detector which has measured and stored the amplitude of the first pulse is then fed into a “reference percentage voltage generator,” the function of which is to provide predetermined ratios of the peak amplitude of the first positive pulse (ratios “predetermined” to be either 15%, 30%, 45%, 60%, 80%, 100%). Each of the outputs of the “reference percentage voltage generator” is fed into the appropriate “comparator” circuit corresponding to the particular polarity and relative magnitude of the outputs. The comparator circuits then measure the amplitudes detected at T2-T8 as positive or negative ratios of the first positive pulse. The results of these comparisons are translated into digital (discrete or non-continuous) signals, which can be utilized to generate signals identifying the waveform and consequently the character in question. At the termination of the scanning, reading and identification a reset signal, at time interval Tg, resets the mechanism for reading of the next character. P.Ex. 14; Schwartz Tr. 121-129 (Second Volume), 158, 159, 170-171. THE DEFENDANT AND THE ACCUSED DEVICE ORS was incorporated on August 22, 1969, for the purpose of manufacturing and selling optical character recognition equipment. This equipment was primarily intended for reading the stylized characters (E-13B characters) which appear on bank checks and the like and which are printed with magnetizable ink. The ORS optical reader did not depend upon the magnetic properties of the E-13B characters for recognition but upon their opticál properties. ORS decided in early 1971 to add a MICR reader to its optical equipment. In March, 1971, James S. Bauer was hired by ORS as a consultant to develop a MICR reader suitable for use in conjunction with the ORS optical equipment, and ORS installed its first magnetic reader in July, 1971. Tyburski Tr. 448-456; P.Ex. 1. It is this reader and those subsequently manufactured and sold by ORS (designated by ORS as the “OCR-71”) that is the accused device in the present litigation. ORS: The apparatus, being a combination Optical and Magnetic Ink Character Recognition System, makes possible two independent readings of characters in a single pass of a document. P.Ex. 18, j[ 1.01. The document passes under a permanent ceramic magnet mounted in the device’s double feed detector assembly which magnetizes the ferrite-impregnated ink of the E-13B characters as they pass through the magnet’s flux field. 1.0.2. After the document characters have been magnetized, they are transported to the magnetic read head which is of the conventional audio-tape-recording type. The magnetic characteristics imparted to the ink by the permanent magnet are then picked up by the reading head which generates an analog voltage signal indicative of the changes in flux fields recorded on the characters by the permanent magnet. As. documents pass under the magnetic read head, individual characters will be detected as unique patterns of field strengths and polarities. The signal thereby generated is amplified by frequency sensitive amplifiers directed at providing an output normalizing signal in the order of a few volts, which is substantially free of noise and distortion, jflí 2.1.1, 2.1.2; MICR Board, Sheet 1 of 1; DF # 6. The start of a character is sensed not from the leading edge of the analog amplified signal, but from a sensing of the first peak output. This pulse serves as a synchronizing start signal which activates the circuitry to measure the field amplitudes and polarity. The actual analog signal, is compared to a like signal which has been passed through a time-lag circuit, and comparison occurs when the difference of the two signals goes negative. Thus, the start signal derived therefrom cannot actually occur until the analog signal itself begins to drop from its peak value; it is derived from the point marking the first peak of the analog signal. (See diagram below.) The sharpness and precision of the start time, therefore, depend on how sharply peaked the sensed signal is. j[ 2.2.1; Fig. 1, MICR Board 1, Sheet 2 of 2. The start signal is fed to a timing circuit which generates two sets of timing pulses: a set of seven long pulses corresponding to the seven possible intervals during which the analog signal may have a flux-change pulse in it; and within each of these seven intervals, a set of sixteen shorter pulses which serve to time various parts of the recognition process. ¡¡2.6.1, 2.8.2, 2.8.3; MICR Board 4, Sheets 1 and 2. Because the first time-period of the analog output will always have a flux-change signal (i.e., the one which signals character starting), the following seven time periods are used to sense the particular character being scanned. The signal actually sensed in one time period is used as a reference in the next time period. The seven sample period measures are taken by three separate comparator circuits, respectively making “small,” “medium,” and “no change” comparisons. If a comparison proves that the amplitude of the signal during one time interval is at least 50% of the value during the previous time interval, and opposite in polarity (assume that the first signal was positive, the second negative), the —M comparator will register. If the first signal has been negative, the + M comparator would indicate the second. Similarly, the ±S comparator measures signals which are at least +40% of the previous signal, and the +NC (no change) comparator measures signals which are at least 70% as high as the previous ones. ffff 1.0.5, 2.3.3, 2.3.2, 2.-3.1, MICR Board 2, Sheets 1-3. Each comparator is a circuit which can (a) store on a capacitor a positive voltage for reference; (b) store on another capacitor a negative voltage for reference; (c) selectively discharge one or the other of the two capacitors to permit a new (and perhaps smaller) reference voltage to be introduced; and (d) produce comparator output signals e.g., +M. There are thus three separate circuits for comparison, differing only in detail, ff 2.3.3 MICR Board 2, Sheets 1-3. The measurements derived from the comparators are combined and stored during the period in which the character is passing under the head of the apparatus. At the completion of the pass of the character, and consequently at the completion of the waveform, the character is identified by a series of logical gates. Beam Tr. 513. When a particular character’s unique feature combination is detected, that is, when the polarity and amplitude criteria for an E-13B character are satisfied during the sampling of a character’s waveform, a 4-bit binary code is developed to represent the E-13B character, jf 1.0.1. Other circuitry in the ORS system carries out the necessary steps of making the identified characters available to a computer system. 1.0.5; MICR Recognition Interface, MICR Board 6, Sheets 2 of 3, MICR Board 7, Sheets 1 & 2. This allows the system’s programmer to analyze data captured by both the optical and magnetic ink reading methods in order to minimize character substitution and rejection while maximizing character acceptance. If 1.0.1. I. VALIDITY: (1) Presumption of Validity: The plaintiff is entitled to and does rely on the presumption of validity of its patent which arises under 35 U.S. C. § 282. Blumcraft of Pittsburgh v. Citizens & Southern Nat. Bank, 407 F.2d 557 (4th Cir. 1969), cert. denied, 395 U.S. 961, 89 S.Ct. 2103, 23 L.Ed.2d 747 (1969), reh. denied, 396 U.S. 870, 90 S.Ct. 39, 24 L.Ed.2d 125 (1969), reh. denied, 396 U.S. 949, 90 S.Ct. 369, 24 L.Ed.2d 254 (1969). That presumption remains in effect until rebutted by the party attacking the validity of the patent. Graham v. John Deere Co., 383 U.S. 1, 86 S.Ct. 684, 15 L.Ed.2d 545 (1966); Westinghouse Co. v. Formica Co., 266 U.S. 342, 45 S.Ct. 117, 69 L.Ed. 316 (1924). The attacker’s burden of proof is a heavy one. Technograph Printed Circuits, Ltd. v. Bendix Aviation Corp., 218 F.Supp. 1 (D.C.M.D.1963), aff’d 327 F.2d 497 (4th Cir.), cert. denied, 379 U.S. 826, 85 S.Ct. 53, 13 L.Ed.2d 36 (1964). The defendant, to rebut the presumption of validity, relies on Perotto as the most pertinent prior art; the failure of the Examiner to make reference to it in the Dykaar file; and the effect of Section 707.05(b) of the Manual of Patent Examining Procedure. According to ORS, these demonstrate that the most pertinent prior art, Perotto, was not considered, and, therefore, the presumption fails. Marston v. J. C. Penney Co., 353 F.2d 976 (4th Cir. 1965), cert. denied, 385 U.S. 974, 87 S.Ct. 515, 17 L.Ed.2d 437 (1966). This would require further examination of the two patents, unaided by any presumption, to determine whether Dykaar was anticipated by Perotto and is therefore invalid and unenforceable against ORS). Lundy argues that the defendant has failed to rebut that presumption and that the presumption is reinforced in those situations where, prior to issuing the patent, the Patent Office “had before it and considered” (emphasis supplied) substantially the same prior art later presented to establish the defense of invalidity. Quoting from Calico Scallopo Corp., et al. v. Willis Brothers, Inc., et al., 171 U.S.P.Q. 476, 478 (E.D.N.C.1971), aff’d, 458 F.2d 390 (4th Cir. 1972), the plaintiff urges that the presumption is strengthened where the “principal references urged against the patent are within the classifications noted as searched, [even though] the asserted patents [are] not noted as pertinent.” The plaintiff also argues that its voluntarily filing of a list of references in its 1967 preliminary amendment which included Perotto strengthens that presumption, and it offers as evidence of consideration that Perotto appears in the same class and subclass as does Dykaar and that that class and subclass was acknowledged to have been considered by the examiner. P.Ex. 13, pp. 35 & 44. Both the plaintiff’s argument in support of the presumption and the defendant’s argument attacking it turn on whether Perotto is the most pertinent prior art and whether it was, in fact, “considered.” It is apparent from Lundy’s stipulation as to the pertinence of Perotto and the reliance of ORS on Perotto that Perotto is the most pertinent prior art against which the Dykaar device must be compared. It is also evident that no reference was made to Perotto by the Examiner in the prosecution of the Dykaar patent. Even though not cited as a reference by the Patent Examiner, there is no presumption in a patent infringement proceeding that patents not cited were overlooked, since they may have been considered and cast aside as not pertinent. Davis v. Buck-Jackson Corp., 138 F.Supp. 908 (E.D.S.C.1955), aff’d, 230 F.2d 655 (4th Cir.), cert. denied, 351 U.S. 950, 76 S.Ct. 846, 100 L.Ed. 1474 (1956). It is as reasonable to conclude that a prior art patent not cited was considered and cast aside because not pertinent, as it is to conclude that it was inadvertently overlooked. However, the question whether the failure of the Examiner to cite certain art is consistent with its examination and rejection depends on the pertinency of the uncited art. Maschinenfabrik Rieter, A. G. v. Greenwood Mills, 340 F.Supp. 1103 (D.C.S.C.1972); Technograph Printed Circuits, Ltd. v. Bendix Aviation Corp., supra. The failure of the Examiner to cite record art which both parties considered to be more pertinent than that in fact cited suggests that the Examiner either did not correctly understand the uncited art or else it was not brought to his attention. Lundy’s reliance on Hazeltine, supra, to strengthen the presumption is misplaced since there was evidence there that the patents asserted against the validity of the patent in suit had been considered. However, the fact that Perotto was cited in Lundy’s preliminary amendment, and the fact that the Patent Office Examiner did search Patent Office Subclass 340-146.3, the same subclass in which Perotto appears, prevents this Court from finding affirmatively that it was not brought to his attention. The Court, unlike the defendant, does not interpret Section 707.05(b) of the Manual of Patent Examining Procedure to mean that unless citations to prior art are presented in the specified form they will be ignored or will not be considered by the Examiner. Nor does the Court read that section to mean that mere failure to cite prior art in the specified form will amount to fraud or misrepresentation. To so construe that section would place the full burden of examination on the shoulders of the applicant. The presumption of validity is greatly weakened by the fact that the Patent Office did not cite Perotto as reference. It was unquestionably part of the prior art and both parties acknowledge that it was highly pertinent, if not the most pertinent prior art. B. F. Goodrich Co. v. United States Rubber Co., 147 F.Supp. 40 (D.C.Md.1956), aff’d, 244 F.2d 468 (4th Cir. 1957); Blumcraft of Pittsburgh v. Citizens & Southern Nat. Bank, supra; Heyl & Patterson, Inc. v. McDowell Co., 317 F.2d 719 (4th Cir. 1963). However, there does remain the question of whether the Examiner recognized the pertinence of Perotto, and because the presumption arising from action of the Patent Office in granting a patent should not be disregarded, especially where intricate questions involved are peculiarly within the competence of experts of the Patent Office, the Court does not find that the presumption is completely destroyed. Merck & Co. v. Olin Mathieson Chemical Corp., 253 F.2d 156 (4th Cir. 1958). The presumption is considerably weakened though, and the Court feels that it must examine the validity of the patent independently and unaided by any presumption. (2) Anticipation: As one of its affirmative defenses, ORS asserts that Dykaar claims 1-4, 9 and 28 are invalid as having been anticipated by the device described in Perotto. 35 U.S.C. § 102. Because 35 U.S.C. § 112 requires that the specifications of a patent must conclude with a claim, the invention in the patent is measured by those claims. Bullard Co. v. General Electric Co., 348 F.2d 985 (4th Cir. 1965). In considering whether Perotto anticipates Dykaar and renders it invalid, the Court must determine whether the first patent, Perotto, shows or describes a device on which the claims of Dykaar read, that is, whether the Perotto device falls within the purview of the Dykaar claims. If for each descriptive phrase in a claim there can be found in the device an element to which the phrase aptly applies, anticipation has occurred; those elements must function in substantially the same way to produce substantially the same result. Straussler v. United States, 339 F.2d 670, 168 Ct.Cl. 852 (1964); Bull v. Logetronics, Inc., 323 F.Supp. 115 (E.D.Va.1971). Both the Perotto device and the Dykaar claims provide for MICR systems which perform their recognition functions by comparing various portions of an individual character’s waveform to reference voltage levels similarly derived from the waveform. Like Dykaar, the device depicted in the exemplary embodiment of Perotto is an “apparatus for the automatic recognition of printed characters . . . wherein each character is scanned for producing a signal having a wave shape characteristic of said character, said character signal being sampled at different time points for producing a plurality of samples which are analyzed to identify said character.” Patent 3,188,611, col. 1, lines 10, 11, 13-15. The plaintiff argues that it is the manner in which this function is accomplished that distinguishes the two patents. The Court agrees that the mere fact that both perform a recognition function does not mean that the one anticipates the other, unless that function is performed in substantially the same way. The operation of the Perotto device may be described as follows: The stylized magnetic ink characters (E-13B font) are magnetized by a magnetizing head and thereafter scanned by a reading head when the character is passed through the air gap of that magnetic pick-up head. The reading head then generates a modulated electrical signal, the form of which is dependent on the distribution of magnetic ink forming the dimensions and shape of the character exposed thereto, and from that modulated signal a character signal is established. The character signal is fed to a squaring circuit which produces a square signal (Patent 3,188,611, Fig. 2) which is continuously generated as long as the amplitude of the signal remains above a predetermined threshold level. During the course of the generation of the character signal, the amplitude of the waveform is sampled at specific points in time relative to the “beginning” of the waveform and stored. Each stored sample is then fed to a separate analog-to-digital converter which compares the incoming sample with percentages of the established “reference amplitude” in order to generate digital signals representing the amplitude of the sample as a percentage of the reference amplitude. The digital signals generated by these comparators are fed to a decoder which generates a signal identifying the character represented by the digital impulses derived from the various sampling times. Construction of Claim: Prior to comparing the claims of the Patent to the device disclosed in Perotto, consideration must be given to the proper construction of those claims, that is, the extent to which those claims are restricted or limited. The plaintiff, during the prosecution of the application in the Patent Office, amended certain claims to include limiting language. In December, 1967, claims 1, 9, 11, 23 and 28, were amended to include language describing a reference voltage level which is “effective” during the generation of timing signals, that amendment having been specifically intended to avoid Perotto. The words “a predetermined portion” were amended to claims 1 and 30 in February, 1970, subsequent to a telephone conversation initiated by the Patent Office Examiner. The plaintiff has chosen to restrict the scope of the claims by amendment in an effort to distinguish them from the prior art. Having done so and having narrowly defined terms in the Patent, the claims will be invalid as anticipated only if the alleged anticipating device falls within the purview of the claims as restricted, whether by definition of terms or by the specifications. The plaintiff defines “a predetermined portion” of a waveform as a portion, the parameters of which are defined in advance such that the portion is recognizable as satisfying these parameters as soon as it is generated. Schwarz Tr. 139-140; PF # 23. A reference voltage level which is derived from the initial portion of a waveform is directly related to a predetermined portion of the waveform within the context of that definition in that it is specified to occur at a certain point in time and at a specific location in the waveform. In the Patent the initial portion has been defined in advance and is immediately recognizable as the initial portion as soon as it is generated. Schwarz Tr. 139, 140; P.Ex. 14, PF # 26. It is the “predetermined portion” contemplated in the Patent. The plaintiff defines a reference voltage level, which is “effective” during the time the timing signals are being generated, as one which must be in existence prior to or at the times that all subsequent timing signals are generated. Schwarz Tr. 373; PF # 27. Although it is clear that both the Perotto device and the Dykaar claims generate at least one reference voltage level and that the reference voltage level so generated is directly related to the waveform, if the Perotto device does not generate a reference voltage level which is directly related to “a predetermined portion” of the waveform and which is “effective” during the time the waveform is sampled (as strictly defined by the plaintiff and the specifications contained in the Patent) there is no anticipation. In Perotto (as in Lundy) voltage measurements of the waveform are made at set time intervals throughout the generation of the waveform. In Perotto the maximum voltage detected in the sampling process is the source of the reference voltage levels. That voltage can occur anywhere in the waveform; it need not correspond to a portion of the waveform where the peaks generated by a typical E-13B character would be expected to occur. Because the portion of a waveform at which the maximum voltage is encountered is not recognizable as such as soon as it occurs, it does not satisfy the plaintiff’s strict definition of “a predetermined portion” and it is not a predetermined portion within the context of the Patent. Schwarz Tr. 398-400; PF #’s 24, 25. In further opposition to the affirmative defense of invalidity by anticipation, the plaintiff relies on the language in the claims that the reference voltage level shall be “effective” during the generation of the timing signals. As previously stated, the plaintiff defines that language to mean that the reference voltage level will be in existence (as a finally determined and known value) when the subsequent timing signals are generated. The defendant argues that as a practical matter neither Perotto nor Dykaar can identify a character until after all of the various timing signals have triggered samplings of the waveform at specific points and those samples have been compared to a reference level arising out of the same waveform, i. e., identification is possible only after the waveform has passed. It is the usefulness of the reference level for purposes of comparison to other specific amplitudes in the waveform that is important, not the fact that it is known or is in existence at the time a sampling pulse is generated. The limitation or definition urged by the plaintiff appears on first analysis to be insignificant or irrelevant as a practical matter but for the fact that it does distinguish the Dykaar claims from the Perotto device. Unless defined in this way, the language would read on the Perotto device and the Patent claims containing that language could not rely thereon to differentiate them from Perotto and thereby avoid anticipation. Whether the comparisons take place at the time of the sampling or later is immaterial as long as each sample, when compared, is compared to a common reference point, and as long as each sample so compared is representative of a certain portion of the waveform from which that reference level was established. Therefore, the truly significant requirement would appear to be that the reference voltage level be generated from the same waveform as that from which are derived the samples to be compared to it, and that the reference level be established and operable as a common reference point for all the samples gathered in the course of a scan whether comparison occurs at the instant the sample is taken or later, after the>sample has been stored. The plaintiff intended the definition of “effective” to be “existent,” and although that definition, on first analysis, would appear to distinguish the claims containing the language from the device described in Perotto only as to form and not as to substance, the requirement that the reference voltage level be in existence during the timing pulses does more. That is, it further identifies the source of the reference voltage level as being the first sampling period or timing pulse; it further identifies “a predetermined portion.” It is to that extent that the language acquires substance and serves to distinguish the claims of the Patent from the prior art device described in Perotto. Since the Perotto device employs as reference voltages certain percentages of the maximum amplitude generated in a character’s electrical signal, the reference voltage cannot be established until the entire character has been scanned (after the generation of timing pulses). Schwarz Tr. 373; P.Br. 47. Although, once established, it is “effective” or operable for comparison to all of the samples accumulated at the generation of the various timing signals in the course of the scan of the waveform, it cannot be said to be in “existence” during each of the timing pulses. Because this is true, the source of the reference voltage level is in no way restricted as to the time or location in the waveform, and is certainly not restricted to the first positive pulse, as is the case in the Patent. The Court rejects the defendant’s argument that, because the initial pulse of waveforms produced by the E-13B font is commonly the pulse with the maximum amplitude, the system for establishing a reference voltage level employed in the Perotto device, in practice, falls within the purview of the plaintiff’s claims and thereby anticipates those claims. The Supreme Court held in Eibel Co. v. Paper Co., supra, 261 U. S. at 66, 43 S.Ct. at 329: “. . . accidental results, not intended and not appreciated, do not constitute anticipation (citing cases).” Furthermore, since the Court must-construe ambiguous language in favor of validity and in line with the definition urged by the plaintiff and accepted in the Patent Office, it finds that the language in question does limit the source of the reference voltage level in the claims where it appears. The limitation of the source of the reference voltage narrows the opportunity for inaccuracy produced by “noise spikes” and capitalizes on the designed standardization of the waveforms and the predictability of the nature of the information to be found therein. For the reasons stated above, the Court finds that claims 1-4, 9, 11, 23, 24, 28 and 30 do not read on the device disclosed in Perotto and are therefore not invalid as having been anticipated by that disclosure. (3) Claim 11 — Insufficient Disclosure Defense The defendant ORS further attacks the validity of claim 11 alleging that claim 11, in addition to its similarity to claim 1, “adds structure directed to a sorting mechanism such as ‘pockets,’ and ‘pocket gates,’ a structure which is not found in the specification of the patent.” ORS Br. p. 33. The defendant states that the patentee’s attempt to incorporate by reference the necessary apparatus disclosed in the earlier patent No. 3,363,756, col. 1, lines 30-34, was improper and therefore ineffective. It is clear that the material sought to be incorporated by reference was “essential material” as defined by the Manual of Patent Examining Procedure, Section 608.01 (P), but unlike the present form of that section, the provision in effect at the time of the application for the Patent (December, 1965) did not specify that the subject of incorporation must be an established patent at the time of application, as opposed to the time of consideration or allowance of the application. That language merely provided that: “all essential claimed features of an invention must be fully disclosed in an application without depending upon a reference to a co-pending application . . . for completing the disclosure.” In any event, on January 16, 1968, the application containing the subject of incorporation issued as U.S. Patent No. 3,363,756, P. Ex. 15. That was some nine months prior to the Examiner’s initiation of examination procedures on the Patent and was more than two years before the issuance of the Patent. P. Ex. 13. Therefore, at the time of the Examiner’s consideration of the application, the reference was not to a co-pending application but was, in fact, a reference to an existing patent. Because the Patent Commissioner has authority to and did, in this case, issue a patent upon an application wherein the disclosure incorporates by reference and relies on a portion of a disclosure of a then existing patent which was available to the public; because there appears no abuse of discretion in doing so; and because the Examiner did not challenge the adequacy of the disclosure of the sorting apparatus; the Court will not disturb that ruling. General Electric Co. v. Brenner, 132 U.S.App.D.C. 323, 407 F.2d 1258 (1968); Application of Fouche, 439 F.2d 1237, 58 C.C.P.A. 1086 (1971). The incorporation by reference being effective, the claim is not invalid as being without support in the disclosure. (4) The Defense of Obviousness — 35 U. S.C. § 103 ORS asserts that claims 12-16, 23, 24 and 30 of the Patent, although not iden-' tical to the prior art, are invalid under 35 U.S.C. § 103 because the differences between those claims and the prior art were obvious to one skilled in the art at the time of the invention. Under the 35 U.S.C. § 103 requirement of nonobviousness as a condition for patentability, the Court must determine the scope and content of the prior art, the differences between the prior art and the claims at issue, and the level of ordinary skill in the pertinent art. Graham v. John Deere Co., supra. In determining obviousness, several prior art references may be used and features may be taken from each reference to show that the subject matter of the claim as a whole would have been obvious to one of ordinary skill in the art. Spray-Bilt, Inc. v. IngersollRand World Trade Ltd., 350 F.2d 99 (5th Cir. 1965). Furthermore, one of ordinary skill in the art is charged with knowledge of the prior art, and evidence of attempts and failures of others to solve the problem are relevant as indicia of nonobviousness in cases where validity is in doubt. Continental Can Co. v. Crown Cork and Seal Co., 415 F.2d 601 (3d Cir. 1969), cert. denied, 397 U.S. 914, 90 S.Ct. 916, 25 L.Ed.2d 94 (1970); Diversified Products Corp. v. Sports Stores, Inc., 294 F.Supp. 375 (D.C.Md.1968); Porter-Gable Machine Co. v. Black & Decker Mfg. Co., 402 F.2d 517 (4th Cir. 1968), cert. denied, 393 U.S. 1063, 89 S.Ct. 716, 21 L.Ed.2d 706 (1969); Maschinenfabrik Rieter, A. G. v. Greenwood Mills, supra. Before a patent can be declared invalid as having been obvious, the subject matter as a whole must have been obvious at the time of the invention. Hindsight reconstruction of the prior art, in itself, cannot be permitted to establish obviousness, but the prior art must be examined with foresight at a time immediately prior to the invention. “Obviousness” does not mean that one skilled in the art can perceive the solution after it has been found and identified by another. Manville Boiler Co. v. Columbia Boiler Co. of Pottstown, 269 F.2d 600 (4th Cir. 1959), cert. denied, 361 U.S. 901, 80 S.Ct. 208, 4 L.Ed.2d 156 (1959); Maschinenfabrik Rieter, A. G. v. Greenwood Mills, supra. The defendant asserts that the only distinction between claims 12-16, 23, 24 and 30 and the other claims is that the former claims are limited by language requiring that the waveform generated in the recognition process shall’possess polarity (negative and positive characteristics) and that the polarity characteristics as well as the amplitude information of the waveform will be analyzed to identify characters. Conversely the plaintiff relies on that limitation to distinguish the Patent from the prior art. ORS assumes the invalidity of the claims but for the limitation and argues that, to an individual skilled in the art of MICR systems and electronic engineering, it would have been obvious that whether an analog waveform possesses polarity or not depends only on whether the magnetizing head used to magnetize the ink is energized with an AC (alternating current) or a DC signal (direct current). ORS argues further that the fact that an analog waveform derived from or generated by direct current will possess polarity whereas one generated from alternating current will not was a basic understanding of one skilled in the art of electronics of recognition systems. Tr. 340-344. The testimony of both Dr. Schwarz - and Dr. Beam indicate that whether a waveform has polarity or not is of little significance since neither conveys any more information than the other, because each waveform is related to and obtainable from the other by the process of integration or differentiation. Tr. 387-388, 541; 342-344. Additionally, the defendant argues that the use of waveforms with polarity was common in the prior art. Other than Perotto, ORS relies on the Scheidhauer patent No. 3,264,609, the Eckert patent No. 3,168,720, and the Furr, et al., patent No. 3,114,131 to establish that fact. D.Br. pp. 36, 37. The Scheidhauer patent shows in Figure 1 the analog waveforms of the fourteen E-13B characters. In addition to the representation of the E-13B characters, the patent teaches a method of character identification which utilizes both the positive and negative polarity information generated at specific intervals in conjunction with a signal representative of the presence of a plurality of voltages in the waveform at the various taps of the delay line. Although the Scheidhauer specifications do not make use of both polarity and amplitude (or magnitude) information derived from the various “tapping points,” but only polarity and the presence of voltages, the patent acknowledges the usefulness of magnitude information and makes specific reference to the fact that both polarity and amplitude may be employed as comparison factors for identification purposes. Scheidhauer patent, col. 4, lines 13-20. The Eckert patent (D.Ex. 2) was introduced at trial and is relied on in the defendant’s brief to show the existence in the prior art of recognition systems which identify characters from waveforms possessing positive and negative characteristics (polarity) through the comparison of the amplitude of the various peaks relative to each other. Tr. 545-548; D.Br. 37. The Eckert system, rather than relying on the strict polarity characteristics, employs a logic matrix designed to utilize information of relative amplitude between the various peaks. Any positive peak will necessarily be greater in amplitude than any negative peak, any positive voltage of two will be greater than a positive voltage of one, and any negative voltage of one will be greater than a negative voltage of two, etc. In addition, the Furr, et al., patent shows a recognition system which identifies characters solely on the basis of polarity information derived from the analog waveform. D.Ex. 11. The plaintiff counters the defendant’s reliance on these prior art references by stating that Scheidhauer and Eckert are no more pertinent than the prior art considered by the Examiner; that they do not provide a foundation for the defense of obviousness; and that, as to them, the statutory presumption of validity remains intact. Otto v. Koppers Co., 246 F.2d 789 (4th Cir. 1957). In support of this argument the plaintiff states that in its Preliminary Amendment it included references to the Eldredge patent (to which Scheidhauer itself refers), the Furr, et al., patent (relied on by the defendant), and the Trimble, et al., patent (U.S. Patent No. 3,114,132) which discloses a system similar to that disclosed in Eckert. Trimble is the only one of the three which was cited as a reference by the Examiner in the patent. ' Because the Trimble citation indicates the Examiner’s consideration of a system similar to only one of the patents upon which the defendant’s obviousness defense is founded, and because obviousness may be determined only after consideration of all. of the pertinent prior art, the plaintiff cannot rely on a presumption of validity as against the defense of obviousness. Application of Kuderna, 426 F.2d 385, 57 CCPA 1078 (1970); Application of Young, 403 F.2d 754, 56 CCPA 757 (1968). Therefore the Court must examine the other patents in question (the prior art) to determine whether they were searched, and, if searched, whether they were justifiably found not to be pertinent. The Court, after an examination of the prior art (including Perotto which employs a waveform without polarity) and in reliance on the testimony of Drs. Schwarz and Beam, finds that at the time of the Dykaar invention it was obvious to one skilled in the art of electronics and recognition systems that an analog waveform either with or without polarity could be generated depending on the current used to energize the magnetizing head. The Court finds further that, although the form of the waveform may be changed, the substantive information appearing therein does not. The Court agrees with the defendant that if the polarity limitation is the only basis upon which the validity of the claims rests then the claims relying thereon are invalid as obvious. The Court also finds that the defined distinction is not such a critical limitation nor does it constitute such a difference from the prior art as to support a determination of patentability. Storchheim v. Daugherty, 410 F.2d 1393, 56 CCPA 1147 (1969). However, the claims are more substantially limited. On March 7, 1969, the. phrase “of predetermined portions” was amended to claim 12 and, consequently, to its dependent claims. P.Ex. 13, pp. 48, 49, 70. The fact that it was not until then that those, claims were allowed indicates that although the Patent Examiner may have also felt the use of polarity waveforms in the form originally claimed was obvious to those skilled in the art át the time of the application, the Patent Examiner felt that the language, claiming apparatus employing means for generating digital signals representative of both polarity and relative magnitude information as derived from predetermined, portions of the waveform, was not obvious. The Court agrees. Claim 23 and dependent claim 24, in addition to calling for the use of polarity and magnitude information, are further limited to apparatus employing reference voltage levels which are “effective” as discussed previously. Claim 30, in addition to requiring the use of polarity and magnitude information, contains the limiting language “a predetermined portion” and “effective” reference voltage levels as also discussed previously. Therefore each rely on more than a polarity limitation to establish nonobviousness, and the Court finds that they are valid as limited. (5) Claims 12-16 — Defense of Invalidity Because Indefinite — 35 U.S.C. § 112 The defendant complains that the terminology “predetermined reference voltage level” is misdeseriptive and that the use thereof renders the claims invalid. Although the choice of words was not as precise as might be desired the references to “a predetermined reference voltage level” are not indefinite and do not render the claims invalid. A “predetermined . . . level would include, as the plaintiff suggests and Dr. Schwarz testified, a fixed percentage of a certain portion of the waveform. Tr. 400. “Level” is an algebraic value and a “predetermined reference voltage level” can be either an absolute (a fixed amount or voltage) or a percentage. Schwarz Tr. 400, 401. In the context of the Patent it is unlikely that the language would be interpreted to mean an absolute or fixed voltage. The exemplary embodiment employs reference voltages derived as certain percentages of the amplitude of that first positive pulse. It is predetermined that the source will be the first pulse, and that the “levels” will be specific percentages of the amplitude thereof. (6) Defense of Invalidity Because the System, as Disclosed, is Inoperative ORS takes the position that, by not specifically disclosing certain allegedly necessary features or details of the circuitry present in the Lundy reader, the Dykaar patent fails to comply with 35 U.S.C. § 112 and is therefore invalid. Specifically, ORS cites the Patent’s failure to disclose a timing delay system, information as to the width of the sampling pulses, a “strobe pulse,” and a “reject” signal. Furthermore, ORS states that the Patent’s disclosure of an improper reading direction for characters in the embodiment, Fig. 1, is a fatal defect. Fig. 1 of the Patent is a simplified perspective view of the mechanical apparatus for exposing the characters on a document to a transducer. The sample document shown in Fig. 1 is depicted as about to be passed through the reader as the MICR characters thereon are read in a left-to-right direction. MICR characters of the E-13B font are specifically designed to be read in a right-to-left direction. Where an individual skilled in the art could, when reading the Patent, make and use the invention disclosed by the specifications .by using the tools common to and known in the art and “without the necessity of further experiment itself of an inventive nature” then the Patent is not insufficiently disclosed. Henry J. Kaiser Co. v. McLouth Steel Co., 257 F.Supp. 372 (E.D.Mich.1966), citing National Battery Co. v. Richardson Co., 63 F.2d 289, 293 (6th Cir. 1933); Sun Ray Gas Corp. v. Bellows-Claude Neon Co., 49 F.2d 886, 887 (6th Cir. 1931). Because descriptions in patents are addressed to those skilled in the art, an applicant for a patent need not expressly set forth in his specification matters which are commonly understood by persons skilled in the art. Application of Johnson, 282 F.2d 370, 48 CCPA 733 (1960). The sufficiency of a specification must be tested in light of such fact and must be judged by what it conveys to those who are skilled in the art. Application of Nelson, 280 F.2d 172, 47 CCPA 1031 (1960). In Application of Borkowski, 422 F.2d 904 at 908, 57 CCPA 946 (1970), the Court stated: “. ... a specification need not contain a working example if the invention is otherwise disclosed in such a manner that one skilled in the art will be able to practice it without an undue amount of experimentation.” As to the invalidity of the Patent for failure to specifically disclose a timing delay, ORS’s argument overlooks the Section 112 requirement that sufficiency of disclosure must be determined as to one skilled in the art of electronics and MICR systems. The defendant offered evidence only to show that for proper operation of the system a delay in the commencement of timing pulses beyond the threshold level is necessary. Although ORS introduced testimony of one of the inventors that delay is “absolutely” necessary for accurate timing, an examination of the transcript indicates that Dykaar’s statement was directed to the fact that delay is “absolutely” necessary for “accurate timing,” rather than for operation of the device as the defendant argues in its reply brief. Dykaar Dep., Glenhead p. 249; D. Reply Br. 9, 10. The testimony of Dr. Schwarz indicates that the device as disclosed in the Patent, when reading E-13B characters, could operate without a timing delay. Tr. 301, 302, 306, 307, 311. In any event, ORS offered no evidence that one skilled in the art would not recognize the desirability of synchronizing the timing signals with the eight points on the waveform where relevant information with respect to the E-13B character appears. On the contrary, it is clear from the record that one skilled in the art would be familiar with the E-13B character font and would recognize that the waveforms generated by the characters in this font can be expected to show relevant information at or near eight specific points. Bauer Tr. 75, 82, 226; P.Ex. 15A. Furthermore, the Patent, at col. 3, lines 4-27, specifically discloses that the positive and negative pulses (which contain the pertinent information to be derived from the waveform) may occur only at eight distinct times (Tx through T8). P.Ex. 14. The Patent goes on to explain that the timing pulses should be made to occur at these distinct times (col. 3, lines 4-24, 30-62; col. 4, lines 64-67). One skilled in the art would not have any difficulty in adjusting the timing signals to correspond to the times Ti to T8. Lundy’s prior U.S. Patent No. 3,363,756 specifically discusses the desirability of synchronizing the timing pulses with the waveform peaks and sets forth in terms easily understood by one skilled in the art how this synchronization may be accomplished by the use of an initial timing delay. P.Ex. 15; Schwarz Tr. (Second Volume) 102, 115-120. The timing and sampling techniques as employed in the Patent were conventional techniques known to persons skilled in the art who could and would have readily appreciated the desirability of a delay mechanism; and the delay technique necessary to assure accurate timing was itself known in the prior art. Schwarz Tr. 359-364; P.Ex. 15; Schwarz Tr. (Second Volume) 115-120. ORS has not, therefore, established that one skilled in the art would not be able to make and use the invention by reason of the alleged insufficiency of the Patent with respect to an initial timing delay. PF # 58. As to the Patent’s failure to provide information concerning the duration of width of sampling pulses the Patent language would have clearly indicated to one skilled in the art that the purpose or object of the pulses is to permit the sampling of waveform peaks. To do so accurately, it is and would have been readily apparent that • the time lapse must be of such duration that it insures the inclusion of the peak in the area sampled. Surely nothing more than basic adjustment of the described circuitry is required to provide adequate sampling pulses. The Court agrees with the plaintiff’s statement in its post-trial brief at page 25 that “. . . the time duration is a matter of choice and conventional engineering design . . .” and the Court finds that the omission of such information from the specifications is not a defect supporting the invalidity of the Patent. A similar situation arises as to the omission of a description of a “strobe” pulse or other signal which activates the identification or recognition circuitry and tells the system when to look at the information gathered from the waveform. ORS asserts that a gate or strobe signal is necessary to the practice of the invention and that since such a signal is not specifically disclosed in the Patent, the Patent fails to comply with 35 U.S. C. § 112. It is clear from the Patent that pertinent information is to be derived from each of the comparisons made at times T2-T8 and furthermore that this information will be erased by a reset signal at time T9. Patent col. 5, lines 15, 38-47. Thus, to attempt to identify a given character prior to Tg (when the MICR character has not yet completed its pass under the transducer) or after T9 (when all information derived from the waveform will have been erased) would obviously lead to meaningless or inaccurate results in the former instance, and no results in the latter. However, ORS offered no testimony or other evidence that one skilled in the art would not recognize the need for a gate or strobe signal or that recognizing the need for such a signal, he would have any difficulty designing a suitable means for providing such a signal. On the contrary, the record indicates that there are a number of ways in which a gate or strobe signal may be provided. Stein Tr., Feb. 5, 1972, p. 27. The prior Lundy ’756 patent specifically shows this signal as an input to the AND circuits while the commercial Lundy devices apply the gate signal in the decoding logic. P.Ex. 15. One skilled in the art would not, thérefore, have had any difficulty in either recognizing the need for or providing a proper gate or strobe signal, and the plaintiff’s omission of the strobe signal, although it was a significant element, was not a defect fatal