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.

Opinion:
CUMMINGS v. MOORE.
No. 4476.
United States Court of Appeals Tenth. Circuit.
Feb. 4, 1953.
Rehearing Denied March 20, 1953.
Milton W. Hardy, Tulsa, Okl. (Hardy & Hardy, Tulsa, Okl., were with him on the brief), for appellant.
Jack N. Hays, Tulsa, Okl. (G. Ellis Gable and Charles P. Gotwals, Jr., Tulsa, Okl., were with him on the brief), for ap-pellee.
Before PHILLIPS, Chief Judge, and BRATTON and MURRAH, Circuit Judges.
BRATTON, Circuit Judge.
This was an action instituted in the United States Court for Northern Oklahoma by W. D. Moore against William G. Cummings for a declaratory judgment determining and adjudicating that plaintiff was not infringing Letters Patent No. 2,496,381, issued to defendant, and relating to a brush for the application of tool joint dressing in oil field drilling operations. It was alleged in the complaint that both parties to the action were citizens of Oklahoma, and that the cause of action was one arising under the laws of the United States, namely 28 U.S.C. §§ 1338, 2201. It was further alleged that defendant claimed to be the owner of the patent; that he asserted infringement on the part of plaintiff; that plaintiff — not defendant — was the inventor of the brush covered by the patent; and that plaintiff was the equitable owner of the patent and therefore could not be guilty of infringing it. And it was further alleged that defendant had been an employee of plaintiff; that defendant’s duties as such employee were to sell and promote the sale of products of W. D. Moore Company in the oil field business; that in accordance with his duties, defendant called to the attention of plaintiff the need for a brush with which to apply tool joint dressing in drilling operations; that thereupon plaintiff developed and worked out a brush devised for such purpose; that shortly after developing such brush, plaintiff began its manufacture; that it was advertised and sold under the name of W. D. Moore Company, defendant actively engaging in the sale thereof; that defendant secretly and in derogation of his duties as employee of plaintiff applied for a patent on the brush in his name; that the application resulted in the issuance of the patent in suit; that defendant had communicated with customers of plaintiff and W. D. Moore Company stating that he was the inventor and owner of the patent and that plaintiff was infringing it; that customers of plaintiff and W. D. Moore Company had become confused by such statements; that in reliance upon such statements, a number of such customers had stopped ordering such brushes from plaintiff and W. D. Moore Company; that the confusion and loss of sales had caused damage to plaintiff for which he had no adequate remedy at law; and that a controversy existed between the parties in respect to defendant’s claim of infringement. The prayer was that plaintiff be declared and decreed to be the lawful owner of the patent; that plaintiff be declared not guilty of infringing the patent; that defendant be declared and decreed to have no right in the patent; that defendant be required to convey and assign the patent to plaintiff; that defendant be enjoined from interfering with plaintiff’s production and sale of the brush; that defendant be further enjoined from manufacturing, producing, selling, and distributing the brush; and that defendant be required to account to plaintiff for profits derived from the sale of the brush.
Defendant answered, admitting citizenship of the parties as alleged in the complaint; admitting issuance of the patent and his assertion of infringement on the part of plaintiff; pleading that all other matters and allegations contained in the complaint were compromised and settled by written agreement of the parties, a copy of the agreement being attached to the answer; pleading that there was another action between the parties arising out of the same subject matter pending in the state court and that precedence in the trial of the two cases should be accorded the state court; and pleading that the court was without jurisdiction of the alleged cause of action set forth in the complaint and of the parties to the action.
The court found that the defendant claimed to be the sole inventor of the brush; that he had charged plaintiff with the infringement of the patent; and that defendant was not the sole inventor of the brush referred to in the patent. The court concluded that the action was one for a declaratory judgment under the patent laws of the United States; that the court had' jurisdiction of the subject matter of the action and of the parties thereto; that since defendant was not the sole inventor of the brush, the patent was void and conferred no rights; and that an invalid patent may not be infringed. Judgment was entered accordingly, and defendant appealed. For convenience, continued reference will be made to the parties as plaintiff and defendant, respectively.
The jurisdiction of the trial court of the subject matter of the action is challenged. It is argued that a complaint alleging breach of confidential relation in patent matters, without alleging diversity of citizenship and the requisite amount in controversy, fails to state a cause of action of which a United States Court has jurisdiction under the patent laws or under the Declaratory Judgment Act. In the absence of diversity of citizenship with the requisite amount in controversy, a United States Court does not have jurisdiction under the patent laws of an action in which the gravamen of the claim pleaded in the complaint is that a confidential relation existed between plaintiff and defendant; that in wrongful disregard of the relation defendant obtained a patent upon the invention of plaintiff; that defendant is trustee ex maleficio for plaintiff in respect to the ownership of the patent; and that defendant should be required to deliver o to plaintiff an assignment of such patent. The general equitable right of plaintiff in an action solely and exclusively of that nature is independent of the patent laws. Becher v. Contoure Laboratories, Inc., 279 U.S. 388, 49 S.Ct. 356, 73 L.Ed. 527; Eckert v. Braun, 7 Cir., 155 F.2d 517. Defendant places strong reliance upon that general principle to defeat jurisdiction of the court; but for reasons presently apparent, it has no application here.
It is essential to the validity of a patent that it be issued upon the application of the one who is the original inventor. A patent issued upon the application of one who is not the original inventor is unauthorized by law, is void, and does not confer any right or title upon the patentee. Atlantic Works v. Brady, 107 U.S. 192, 2 S.Ct. 225, 27 L.Ed. 438; Kennedy v. Hazelton, 128 U.S. 667, 9 S.Ct. 202, 32 L.Ed. 576. And an invalid patent cannot be infringed. M. Swift & Sons v. W. H. Coe Manufacturing Co., 1 Cir., 102 F.2d 391; Cridlebaugh v. Rudolph, 3 Cir., 131 F.2d 795, certiorari denied, 318 U.S. 799, 63 S.Ct. 855, 87 L.Ed. 1147; International Carbonic Engineering Co. v. Natural Carbonic Products, D.C., 57 F.Supp. 248, affirmed, 9 Cir., 158 F.2d 285; Miehle Printing Press 6 Manufacturing Co. v. Publication Corp., 7 Cir., 166 F.2d 615.
In the course of pre-trial conferences and at the beginning of the trial, plaintiff effectively abandoned the allegations of his complaint concerning a confidential relation between the parties, concerning a breach of such relation on the part of defendant in seeking and obtaining the patent, concerning plaintiff’s equitable ownership of the patent and his right to an assignment of it, and concerning the liability of defendant in damages. By statements too plain for misunderstanding, plaintiff made it clear that he merely sought a declaratory judgment of non-infringement of the patent for the reason that defendant was not the original inventor of the brush and therefore the patent could not be infringed, together with injunctive relief restraining defendant from continued injury to the business of plaintiff by assertions of ownership of the patent and its infringement. The allegations not abandoned and remaining in the complaint that the patent issued to defendant was void and not capable of being infringed for the reason that defendant was not the original inventor; that defendant wrongfully asserted infringement on the part of plaintiff; and that wrongful assertion of infringement made to customers and prospective customers of plaintiff had injured and was continuing to injure the business of plaintiff and of W. D. Moore Company with resulting damage, stated a justiciable cause of action arising under the patent laws of the United States for which the court was clothed with jurisdiction to grant appropriate relief under the Declaratory Judgment Act, even though there was a lack of diversity of citizenship. Grip Nut Co. v. Sharp, 7 Cir., 124 F.2d 814; Aralac, Inc. v. Hat Corporation of America, 3 Cir., 166 F.2d 286; Hook v. Hook & Ackerman, 3 Cir., 187 F.2d 52.
The sufficiency of the evidence to support the finding of the trial court that defendant was not the original inventor of the brush is challenged. The grant of letters -patent raised a prima facie presumption that defendant was the inventor of the brush, and the burden rested upon plaintiff to show otherwise by evidence which was clear, strong, and convincing. It would not serve any useful purpose to detail the evidence at .length. It is enough to say that a painstaking review of the record leaves little room for doubt that the evidence adduced upon the trial met in full measure the exacting requirements in a case of this kind.
Certain settlement proceedings are relied upon as constituting a recognition of rights in the defendant to the manufacture and sale of the brush prior and paramount to any rights of plaintiff. Four proposed drafts of an agreement of settlement were prepared by one or the other of the attorneys then representing the parties, respectively, but the authorship or source of each document as distinguished from the others is not entirely clear. Three of the proposed drafts were not executed by either party. The fourth was signed by both of them and it became effective. The attorney who then represented defendant testified that in the negotiations had in connection with the preparation of the several drafts of agreement, the brush was discussed; that it was the understanding that in return for the release of certain claims being asserted by defendant, plaintiff released any interest he had in the brush; and that in the absence of such release on the part of the plaintiff, defendant would not have executed the agreement. The attorney representing plaintiff testified differently. The agreement signed by the parties did not contain any provision recognizing any right of defendant in the manufacture and sale of the brush which was prior and paramount to the right of plaintiff. It did not contain any provision subordinating, releasing, surrendering, or extinguishing any right of plaintiff in the manufacture and sale of the brush. The instrument will be searched in vain for any provision of that kind. The contention that the settlement proceedings constituted a recognition of rights in defendant superior to those of plaintiff relating to the manufacture and sale of the brush finds no support in the record.
Defendant seeks to invoke the doctrine of estoppel. He asserts that previous litigation between the parties estops plaintiff from attacking the validity of the patent. In its answer, defendant pleaded that a certain case was pending in the state court; that it was instituted prior to the filing of this action; and that'precedence in the trial of the two cases should be accorded the state court. But estoppel was not pleaded.* The answer was completely silent in respect to such an issue. Estoppel is an affirmative defense which must be pleaded. And if not pleaded, it is waived. Zeligson v. Hartmen-Blair, Inc., 10 Cir., 135 F.2d 874; Bowles v. Capitol Packing Co., 10 Cir., 143 F.2d 87; Tornello v. Deligiannis Brothers, 7 Cir., 180 F.2d 553.
Other contentions advanced by defendant have been examined, and we think they are without merit.
The judgment is affirmed.

Question: What is the total number of appellants in the case that fall into the category "private business and its executives"? Answer with a number.

Choices:

Answer: 1