opinion: William R. BLAIR, Jr., Appellant, v. DOWD’S, INC., et al. William R. BLAIR, Jr. v. DOWD’S, INC., Westinghouse Electric Corporation, Appellant.
  Nos. 22760, 22761.
  United States Court of Appeals, District of Columbia Circuit.
  Argued March 12, 1970.
  Decided Aug. 27, 1970.
  Mr. Marshall A. Lerner, with whom Messrs. William D. Hall and Elliott I. Pollock, Washington, D. C., were on the brief, for appellant in No. 22,760 and ap-pellee in No. 22,761.
  Mr. Edward F. McKie, Jr., with whom Mr. Albert J. Santorelli, Washington, D. C., was on the brief, for appellees in No. 22,760 and appellant in No. 22,761.
  Before TAMM, ROBINSON and Mac-KINNON, Circuit Judges.
  PER CURIAM:
  The subject matter of the instant patent litigation is a complex bit of electronic circuitry found in the viscera of the common television set. In television receivers, the picture is reconstituted from the stream of information broadcast over the airwaves by means of a beam of electrons scanning rapidly and continuously, line by line, over a cathode ray picture tube. In addition to this “video” or picture information, the broadcast signal contains audio information which becomes the sound portion of a television program and synchronizing (“synch”) signals which regulate the scanning operation of the electron beam. Synch signals are separated from the general flow of broadcast information and made available for the task of controlling the electron beam by means of a device which is prosaically denominated a “synch separator.” Efficient operation of the synch separator is made difficult by “noise” or interference generated by any electrical equipment which produces sparks while in operation; if the synch separator is unable to distinguish these unwanted signals from the essential synch signals, the result is, as might be expected, a substantial degradation of picture quality.
  The patent in question, No. 2,783,377, was issued to Wofford on February 26, 1957, on an application originally filed in 1951. (J.A. 1115.) The Wofford patent employs a device known as a noise inverter, which was common in the prior art, to eliminate the undesired noise by applying to the circuit an electrical signal of the opposite polarity which cancels the offending interference. The claimed invention in the Wofford patent, however, resides in the fact that in his circuit when the synch separator operates to remove the synch signals from the other broadcast information, it creates a complex “bias voltage” which is then used to control the noise inverter, thereby allegedly making the inverter more responsive to a wider range of noise levels than comparable devices known to the art in 1951.
  Appellant Blair, the present owner of the Wofford patent, brought suit for infringement in the District Court, naming Dowd’s, Inc. as defendant (J.A. 11-12); thereafter Westinghouse, Inc., manufacturer of the allegedly infringing television sets sold by Dowd’s, intervened as a defendant in the action, contesting the issue of infringement and asserting as an affirmative defense the invalidity of the Wofford patent. (J.A. 14-18.) After a lengthy trial at which voluminous testimony and numerous exhibits were introduced, the District Court ruled that the Wofford patent was invalid because it was obvious within the meaning of 35 U.S.C. § 103 (1964), but that if the Wofford circuitry were deemed patentable, it would .have been infringed by Westinghouse. (J.A. 1115-32.) In the present cross-appeals, Blair contests the trial court’s holding on the question of obviousness, whereas Westinghouse attacks the finding on infringement. We affirm.
  There can be little doubt that the trial court applied the correct principles of law in passing upon the obviousness of the claimed invention. After summarizing the evolution of the statutory criterion, the trial judge pointed out that the Wofford patent was a combination claim, and observed that the Supreme Court had cautioned that “[cjourts should scrutinize combination patent claims with a care proportioned to the difficulty and improbability of finding invention in an assembly of old elements.” Great Atlantic & Pacific Tea Co. v. Supermarket Equip. Corp., 340 U. S. 147, 152, 71 S.Ct. 127, 130, 95 L.Ed. 162 (1950). The continuing, if not increased, vitality of this proposition is underscored by several recent decisions; see, e. g., Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 61, 90 S.Ct. 305, 308, 24 L.Ed.2d 258 (1969) (combination claim must produce an “effect greater than the sum of the several effects taken separately” or a “synergistic result” in order to be patentable); Lear, Inc. v. Adkins, 395 U.S. 653, 670, 89 S.Ct. 1902, 1911, 23 L.Ed.2d 610 (1969) (courts should protect “the important public interest in permitting full and free competition in the use of ideas which are in reality a part of the public domain”); International Salt Co. v. Commissioner of Patents, 140 U.S. App.D.C. 378, 436 F.2d 126 (D.C.Cir. April 15, 1970).
  The trial court then proceeded to determine as questions of fact the content of the prior art which was in existence at the time Wofford sought his patent, and the differences between the prior art and the claimed invention, as required by Graham v. John Deere Co., 383 U.S. 1, 17, 86 S.Ct. 684, 15 L.Ed.2d 545 (1966). Specifically, the trial court found that a patent application by Anderson, filed before Wofford’s application, “discloses every feature shown in the patent at suit except the connection between the synchronizing separator and the noise inverter”; that the prior art was familiar with “the use of voltage originating in one part of the receiver for the control or operation of another part of the receiver”; that a patent issued to Schlesinger in 1940 “shows the use of voltage originating in the synchronizing separator to control another part of the receiver”; and that a patent issued to Holmes in 1942 “discloses a noise inverter which is operated by voltage derived from another part of the television receiver, in this case the detector circuit.” (J.A. 1125.) On the basis of these and other findings, the trial court concluded that Wofford’s circuit was “obvious and the product of mechanical skill rather than of the inventive faculty.” (J.A. 1126.) Appellant Blair argues at great length and in considerable technical detail that the Wofford patent constitutes a substantial departure from the prior art and that the trial court’s findings in this area are so defective as to mandate reversal. However, our review of the record reveals that the foregoing findings are amply supported by the evidence, and that the trial court’s ultimate conclusion — that the Wofford circuit is unpatentable by virtue of its obviousness —is fully in accord with applicable principles of law.
  Other contentions advanced by the appellant Blair do not merit discussion in this opinion, and, in view of our disposition of the issue of obviousness, we need not pass upon the challenges by appellant Westinghouse to the trial court’s findings and conclusions on the issue of infringement. Accordingly, the judgment of the District Court is affirmed.
  Affirmed.
instruction: What follows is an opinion from a United States Court of Appeals.
  Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
  In some cases there is some confusion over who should be listed as the appellant and who as the respondent. This confusion is primarily the result of the presence of multiple docket numbers consolidated into a single appeal that is disposed of by a single opinion. Most frequently, this occurs when there are cross appeals and/or when one litigant sued (or was sued by) multiple litigants that were originally filed in district court as separate actions. The coding rule followed in such cases should be to go strictly by the designation provided in the title of the case. The first person listed in the title as the appellant should be coded as the appellant even if they subsequently appeared in a second docket number as the respondent and regardless of who was characterized as the appellant in the opinion.
  To clarify the coding conventions, consider the following hypothetical case in which the US Justice Department sues a labor union to strike down a racially discriminatory seniority system and the corporation (siding with the position of its union) simultaneously sues the government to get an injunction to block enforcement of the relevant civil rights law. From a district court decision that consolidated the two suits and declared the seniority system illegal but refused to impose financial penalties on the union, the corporation appeals and the government and union file cross appeals from the decision in the suit brought by the government. Assume the case was listed in the Federal Reporter as follows:
  United States of America,
  Plaintiff, Appellant
  v
  International Brotherhood of Widget Workers,AFL-CIO
  Defendant, Appellee.
  International Brotherhood of Widget Workers,AFL-CIO
  Defendants, Cross-appellants
  v
  United States of America.
  Widgets, Inc. & Susan Kuersten Sheehan, President & Chairman
  of the Board
  Plaintiff, Appellants,
  v
  United States of America,
  Defendant, Appellee.
  This case should be coded as follows:Appellant = United States, Respondents = International Brotherhood of Widget Workers Widgets, Inc., Total number of appellants = 1, Number of appellants that fall into the category "the federal government, its agencies, and officials" = 1, Total number of respondents = 3, Number of respondents that fall into the category "private business and its executives" = 2, Number of respondents that fall into the category "groups and associations" = 1.
  Note that if an individual is listed by name, but their appearance in the case is as a government official, then they should be counted as a government rather than as a private person. For example, in the case "Billy Jones & Alfredo Ruiz v Joe Smith" where Smith is a state prisoner who brought a civil rights suit against two of the wardens in the prison (Jones & Ruiz), the following values should be coded: number of appellants that fall into the category "natural persons" =0 and number that fall into the category "state governments, their agencies, and officials" =2. A similar logic should be applied to businesses and associations. Officers of a company or association whose role in the case is as a representative of their company or association should be coded as being a business or association rather than as a natural person. However, employees of a business or a government who are suing their employer should be coded as natural persons. Likewise, employees who are charged with criminal conduct for action that was contrary to the company policies should be considered natural persons.
  If the title of a case listed a corporation by name and then listed the names of two individuals that the opinion indicated were top officers of the same corporation as the appellants, then the number of appellants should be coded as three and all three were coded as a business (with the identical detailed code). Similar logic should be applied when government officials or officers of an association were listed by name.
  Your specific task is to determine the total number of appellants in the case that fall into the category "private business and its executives". If the total number cannot be determined (e.g., if the appellant is listed as "Smith, et. al." and the opinion does not specify who is included in the "et.al."), then answer 99.