Task: sc_petitioner

What follows is an opinion from the Supreme Court of the United States. Your task is to identify the petitioner of the case. The petitioner is the party who petitioned the Supreme Court to review the case. This party is variously known as the petitioner or the appellant. Characterize the petitioner as the Court's opinion identifies them.

Identify the petitioner by the label given to the party in the opinion or judgment of the Court except where the Reports title a party as the "United States" or as a named state. Textual identification of parties is typically provided prior to Part I of the Court's opinion. The official syllabus, the summary that appears on the title page of the case, may be consulted as well. In describing the parties, the Court employs terminology that places them in the context of the specific lawsuit in which they are involved. For example, "employer" rather than "business" in a suit by an employee; as a "minority," "female," or "minority female" employee rather than "employee" in a suit alleging discrimination by an employer.

Also note that the Court's characterization of the parties applies whether the petitioner is actually single entity or whether many other persons or legal entities have associated themselves with the lawsuit. That is, the presence of the phrase, et al., following the name of a party does not preclude the Court from characterizing that party as though it were a single entity. Thus, identify a single petitioner, regardless of how many legal entities were actually involved. If a state (or one of its subdivisions) is a party, note only that a state is a party, not the state's name.

Mr. Justice Clark
delivered the opinion of the Court.
The question before us is whether the maintenance and enforcement of a patent obtained by fraud on the Patent Office may be the basis of an action under § 2 of the Sherman Act, and therefore subject to a treble damage claim by an injured party under § 4 of the Clayton Act. The respondent, Food Machinery & Chemical Corp. (hereafter Food Machinery), filed this suit for infringement of its patent No. 2,328,655 covering knee-action swing diffusers used in aeration equipment for sewage treatment systems. Petitioner, Walker Process Equipment, Inc. (hereafter Walker), denied the infringement and counterclaimed for a declaratory judgment that the patent was invalid. After discovery, Food Machinery moved to dismiss its complaint with prejudice because the patent had expired. Walker then amended its counterclaim to charge that Food Machinery had “illegally monopolized interstate and foreign commerce by fraudulently and in bad faith obtaining and maintaining ... its patent . . . well knowing that it had no basis for ... a patent.” It alleged fraud on the basis that Food Machinery had sworn before the Patent Office that it neither knew nor believed that its invention had been in public use in the United States for more than one year prior to filing its patent application when, in fact, Food Machinery was a party to prior use within such time. The counterclaim further asserted that the existence of the patent had deprived Walker of business that it would have otherwise enjoyed. Walker prayed that Food Machinery’s conduct be declared a violation of the antitrust laws and sought recovery of treble damages.
The District Court granted Food Machinery’s motion and dismissed its infringement complaint along with Walker’s amended counterclaim, without leave to amend and with prejudice. The Court of Appeals for the Seventh Circuit affirmed, 335 F. 2d 315. We granted cer-tiorari, 379 U. S. 957. We have concluded that the enforcement of a patent procured by fraud on the Patent Office may be violative of § 2 of the Sherman Act provided the other elements necessary to a § 2 case are present. In such event the treble damage provisions of § 4 of the Clayton Act would be available to an injured party.
I.
As the case reaches us, the allegations of the counterclaim, as to the fraud practiced upon the Government by Food Machinery as well as the resulting damage suffered by Walker, are taken as true. We, therefore, move immediately to a consideration of the legal issues presented.
Both Walker and the United States, which appears as amicus cunde, argue that if Food Machinery obtained its patent by fraud and thereafter used the patent to exclude Walker from the market through “threats of suit” and prosecution of this infringement suit, such proof would establish a prima facie violation of § 2 of the Sherman Act. On the other hand, Food Machinery says that a patent monopoly and a Sherman Act monopolization cannot be equated; the removal of the protection of a patent grant because of fraudulent procurement does not automatically result in a § 2 offense. Both lower courts seem to have concluded that proof of fraudulent procurement may be used to bar recovery for infringement, Precision Instrument Mfg. Co. v. Automotive Maintenance Machinery Co., 324 U. S. 806 (1945), but not to establish invalidity. As the Court of Appeals expressed the proposition, “only the government may ‘annul or set aside’ a patent,” citing Mowry v. Whitney, 14 Wall. 434 (1872). It went on to state that no case had “decided, or hinted that fraud on the Patent Office may be turned to use in an original affirmative action, instead of as an equitable defense. . . . Since Walker admits that its anti-trust theory depends on its ability to prove fraud on the Patent Office, it follows that . . . Walker’s second amended counterclaim failed to state a claim upon which relief could be granted.” 335 F. 2d, at 316.
II.
We have concluded, first, that Walker’s action is not barred by the rule that only the United States may sue to cancel or annul a patent. It is true that there is no statutory authority for a private annulment suit and the invocation of the equitable powers of the court might often subject a patentee “to innumerable vexatious suits to set aside his patent.” Mo wry, supra, at 441. But neither reason applies here. Walker counterclaimed under the Clayton Act, not the patent laws. While one of its elements is the fraudulent procurement of a patent, the action does not directly seek the patent’s annulment. The gist of Walker’s claim is that since Food Machinery obtained its patent by fraud it cannot enjoy the limited exception to the prohibitions of § 2 of the Sherman Act, but must answer under that section and § 4 of the Clayton Act in treble damages to those injured by any monopolistic action taken under the fraudulent patent claim. Nor can the interest in protecting patentees from “innumerable vexatious suits” be used to frustrate the assertion of rights conferred by the antitrust laws. It must be remembered that we deal only with a special class of patents, i. e., those procured by intentional fraud.
Under the decisions of this Court a person sued for infringement may challenge the validity of the patent on various grounds, including fraudulent procurement. E. g., Precision Instrument Mfg. Co. v. Automotive Maintenance Machinery Co., 324 U. S. 806 (1945); Hazel-Atlas Co. v. Hartford-Empire Co., 322 U. S. 238 (1944); Keystone Driller Co. v. General Excavator Co., 290 U. S. 240 (1933). In fact, one need not await the filing of a threatened suit by the patentee; the validity of the patent may be tested under the Declaratory Judgment Act, 28 U. S. C. § 2201 (1964 ed.). See Kerotest Mfg. Co. v. C-O Two Fire Equipment Co., 342 U. S. 180, 185 (1952). At the same time, we have recognized that an injured party may attack the misuse of patent rights. See, e. g., Mercoid Corp. v. Mid-Continent Investment Co., 320 U. S. 661 (1944). To permit recovery of treble damages for the fraudulent procurement of the patent coupled with violations of § 2 accords with these long-recognized procedures. It would also promote the purposes so well expressed in Precision Instrument, supra, at 816:
“A patent by its very nature is affected with a public interest. ... [It] is an exception to the general rule against monopolies and to the right to access to a free and open market. The far-reaching social and economic consequences of a patent, therefore, give the public a paramount interest in seeing that patent monopolies spring from backgrounds free from fraud or other inequitable conduct and that such monopolies are kept within their legitimate scope.”
III.
Walker’s counterclaim alleged that Food Machinery obtained the patent by knowingly and willfully misrepresenting facts to the Patent Office. Proof of this assertion would be sufficient to strip Food Machinery of its exemption from the antitrust laws. By the same token, Food Machinery’s good faith would furnish a complete defense. This includes an honest mistake as to the effect of prior installation upon patentability — so-called “technical fraud.”
To establish monopolization or attempt to monopolize a part of trade or commerce under § 2 of the Sherman Act, it would then be necessary to appraise the exclusionary power of the illegal patent claim in terms of the relevant market for the product involved. Without a definition of that market there is no way to measure Food Machinery’s ability to lessen or destroy competition. It may be that the device — knee-action swing diffusers — used in sewage treatment systems does not comprise a relevant market. There may be effective substitutes for the device which do not infringe the patent. This is a matter of proof, as is the amount of damages suffered by Walker.
As respondent points out, Walker has not clearly articulated its claim. It appears to be based on a concept of per se illegality under § 2 of the Sherman Act. But in these circumstances, the issue is premature. As the Court summarized in White Motor Co. v. United States, 372 U. S. 253 (1963), the area of per se illegality is carefully limited. We are reluctant to extend it on the bare pleadings and absent examination of market effect and economic consequences.
However, even though the per se claim fails at this stage of litigation, we believe that the case should be remanded for Walker to clarify the asserted violations of § 2 and to offer proof thereon. The trial court dismissed its suit not because Walker failed to allege the relevant market, the dominance of the patented device therein, and the injurious consequences to Walker of the patent’s enforcement, but rather on the ground that the United States alone may “annul or set aside” a patent for fraud in procurement. The trial court has not analyzed any economic data. Indeed, no such proof has yet been offered because of the disposition below. In view of these considerations, as well as the novelty of the claim asserted and the paucity of guidelines available in the decided cases, this deficiency cannot be deemed crucial. Fairness requires that on remand Walker have the opportunity to make its § 2 claims more specific, to prove the alleged fraud, and to establish the necessary elements of the asserted § 2 violation.
Reversed and remanded.
26 Stat. 209, 15 U. S. C. § 2 (1964 ed.):
“Every person who shall monopolize, or attempt to monopolize, or combine or conspire with any other person or persons, to monopolize any part of the trade or commerce among the several States, or with foreign nations, shall be deemed guilty of a misdemeanor . . . .”
38 Stat. 731, 15 U. S. C. § 15 (1964 ed.):
“Any person who shall be injured in his business or property by reason of anything forbidden in the antitrust laws may sue therefor in any district court of the United States in the district in which the defendant resides or is found or has an agent, without respect to the amount in controversy, and shall recover threefold the damages by him sustained, and the cost of suit, including a reasonable attorney’s fee.”
The patent in question was issued in the name of the inventor, Lannert. But he had previously assigned the patent rights to his employer, Chicago Pump Company, a division of Food Machinery.
See, e. g., United States v. New Wrinkle, Inc., 342 U. S. 371, 376 (1952).
This conclusion applies with equal force to an assignee who maintains and enforces the patent with knowledge of the patent’s infirmity.

Question: Who is the petitioner of the case?
年. attorney general of the United States, or his office
数. specified state board or department of education
日. city, town, township, village, or borough government or governmental unit
的. state commission, board, committee, or authority
月. county government or county governmental unit, except school district
用. court or judicial district
成. state department or agency
名. governmental employee or job applicant
时. female governmental employee or job applicant
件. minority governmental employee or job applicant
一. minority female governmental employee or job applicant
请. not listed among agencies in the first Administrative Action variable
中. retired or former governmental employee
据. U.S. House of Representatives
码. interstate compact
不. judge
新. state legislature, house, or committee
文. local governmental unit other than a county, city, town, township, village, or borough
下. governmental official, or an official of an agency established under an interstate compact
分. state or U.S. supreme court
入. local school district or board of education
人. U.S. Senate
功. U.S. senator
上. foreign nation or instrumentality
户. state or local governmental taxpayer, or executor of the estate of
为. state college or university
间. United States
号. State
取. person accused, indicted, or suspected of crime
回. advertising business or agency
在. agent, fiduciary, trustee, or executor
页. airplane manufacturer, or manufacturer of parts of airplanes
字. airline
有. distributor, importer, or exporter of alcoholic beverages
个. alien, person subject to a denaturalization proceeding, or one whose citizenship is revoked
作. American Medical Association
示. National Railroad Passenger Corp.
出. amusement establishment, or recreational facility
是. arrested person, or pretrial detainee
失. attorney, or person acting as such;includes bar applicant or law student, or law firm or bar association
表. author, copyright holder
除. bank, savings and loan, credit union, investment company
加. bankrupt person or business, or business in reorganization
败. establishment serving liquor by the glass, or package liquor store
生. water transportation, stevedore
信. bookstore, newsstand, printer, bindery, purveyor or distributor of books or magazines
类. brewery, distillery
置. broker, stock exchange, investment or securities firm
理. construction industry
本. bus or motorized passenger transportation vehicle
息. business, corporation
行. buyer, purchaser
定. cable TV
改. car dealer
市. person convicted of crime
期. tangible property, other than real estate, including contraband
以. chemical company
修. child, children, including adopted or illegitimate
元. religious organization, institution, or person
方. private club or facility
录. coal company or coal mine operator
区. computer business or manufacturer, hardware or software
单. consumer, consumer organization
位. creditor, including institution appearing as such; e.g., a finance company
型. person allegedly criminally insane or mentally incompetent to stand trial
法. defendant
县. debtor
存. real estate developer
品. disabled person or disability benefit claimant
前. distributor
称. person subject to selective service, including conscientious objector
注. drug manufacturer
值. druggist, pharmacist, pharmacy
输. employee, or job applicant, including beneficiaries of
建. employer-employee trust agreement, employee health and welfare fund, or multi-employer pension plan
能. electric equipment manufacturer
大. electric or hydroelectric power utility, power cooperative, or gas and electric company
例. eleemosynary institution or person
度. environmental organization
始. employer. If employer's relations with employees are governed by the nature of the employer's business (e.g., railroad, boat), rather than labor law generally, the more specific designation is used in place of Employer.
到. farmer, farm worker, or farm organization
面. father
载. female employee or job applicant
点. female
密. movie, play, pictorial representation, theatrical production, actor, or exhibitor or distributor of
动. fisherman or fishing company
果. food, meat packing, or processing company, stockyard
图. foreign (non-American) nongovernmental entity
提. franchiser
发. franchisee
式. lesbian, gay, bisexual, transexual person or organization
国. person who guarantees another's obligations
登. handicapped individual, or organization of devoted to
错. health organization or person, nursing home, medical clinic or laboratory, chiropractor
者. heir, or beneficiary, or person so claiming to be
认. hospital, medical center
误. husband, or ex-husband
接. involuntarily committed mental patient
关. Indian, including Indian tribe or nation
重. insurance company, or surety
第. inventor, patent assigner, trademark owner or holder
地. investor
如. injured person or legal entity, nonphysically and non-employment related
设. juvenile
目. government contractor
开. holder of a license or permit, or applicant therefor
事. magazine
可. male
要. medical or Medicaid claimant
代. medical supply or manufacturing co.
小. racial or ethnic minority employee or job applicant
选. minority female employee or job applicant
标. manufacturer
明. management, executive officer, or director, of business entity
编. military personnel, or dependent of, including reservist
求. mining company or miner, excluding coal, oil, or pipeline company
列. mother
网. auto manufacturer
万. newspaper, newsletter, journal of opinion, news service
最. radio and television network, except cable tv
器. nonprofit organization or business
所. nonresident
内. nuclear power plant or facility
体. owner, landlord, or claimant to ownership, fee interest, or possession of land as well as chattels
通. shareholders to whom a tender offer is made
务. tender offer
此. oil company, or natural gas producer
商. elderly person, or organization dedicated to the elderly
序. out of state noncriminal defendant
化. political action committee
消. parent or parents
否. parking lot or service
保. patient of a health professional
使. telephone, telecommunications, or telegraph company
次. physician, MD or DO, dentist, or medical society
机. public interest organization
对. physically injured person, including wrongful death, who is not an employee
量. pipe line company
查. package, luggage, container
部. political candidate, activist, committee, party, party member, organization, or elected official
性. indigent, needy, welfare recipient
和. indigent defendant
更. private person
后. prisoner, inmate of penal institution
证. professional organization, business, or person
题. probationer, or parolee
确. protester, demonstrator, picketer or pamphleteer (non-employment related), or non-indigent loiterer
格. public utility
了. publisher, publishing company
于. radio station
金. racial or ethnic minority
公. person or organization protesting racial or ethnic segregation or discrimination
午. racial or ethnic minority student or applicant for admission to an educational institution
円. realtor
片. journalist, columnist, member of the news media
空. resident
态. restaurant, food vendor
管. retarded person, or mental incompetent
主. retired or former employee
天. railroad
自. private school, college, or university
我. seller or vendor
全. shipper, including importer and exporter
今. shopping center, mall
来. spouse, or former spouse
正. stockholder, shareholder, or bondholder
说. retail business or outlet
意. student, or applicant for admission to an educational institution
送. taxpayer or executor of taxpayer's estate, federal only
容. tenant or lessee
已. theater, studio
结. forest products, lumber, or logging company
会. person traveling or wishing to travel abroad, or overseas travel agent
段. trucking company, or motor carrier
计. television station
源. union member
色. unemployed person or unemployment compensation applicant or claimant
時. union, labor organization, or official of
交. veteran
系. voter, prospective voter, elector, or a nonelective official seeking reapportionment or redistricting of legislative districts (POL)
过. wholesale trade
电. wife, or ex-wife
询. witness, or person under subpoena
符. network
未. slave
程. slave-owner
常. bank of the united states
条. timber company
当. u.s. job applicants or employees
情. Army and Air Force Exchange Service
口. Atomic Energy Commission
合. Secretary or administrative unit or personnel of the U.S. Air Force
车. Department or Secretary of Agriculture
实. Alien Property Custodian
组. Secretary or administrative unit or personnel of the U.S. Army
版. Board of Immigration Appeals
周. Bureau of Indian Affairs
址. Bonneville Power Administration
记. Benefits Review Board
二. Civil Aeronautics Board
同. Bureau of the Census
业. Central Intelligence Agency
权. Commodity Futures Trading Commission
其. Department or Secretary of Commerce
进. Comptroller of Currency
试. Consumer Product Safety Commission
验. Civil Rights Commission
料. Civil Service Commission, U.S.
传. Customs Service or Commissioner of Customs
述. Defense Base Closure and REalignment Commission
集. Drug Enforcement Agency
多. Department or Secretary of Defense (and Department or Secretary of War)
无. Department or Secretary of Energy
员. Department or Secretary of the Interior
报. Department of Justice or Attorney General
他. Department or Secretary of State
無. Department or Secretary of Transportation
服. Department or Secretary of Education
线. U.S. Employees' Compensation Commission, or Commissioner
这. Equal Employment Opportunity Commission
制. Environmental Protection Agency or Administrator
将. Federal Aviation Agency or Administration
处. Federal Bureau of Investigation or Director
高. Federal Bureau of Prisons
子. Farm Credit Administration
道. Federal Communications Commission (including a predecessor, Federal Radio Commission)
章. Federal Credit Union Administration
手. Food and Drug Administration
库. Federal Deposit Insurance Corporation
三. Federal Energy Administration
从. Federal Election Commission
支. Federal Energy Regulatory Commission
家. Federal Housing Administration
长. Federal Home Loan Bank Board
付. Federal Labor Relations Authority
秒. Federal Maritime Board
路. Federal Maritime Commission
完. Farmers Home Administration
象. Federal Parole Board
则. Federal Power Commission
现. Federal Railroad Administration
京. Federal Reserve Board of Governors
转. Federal Reserve System
辑. Federal Savings and Loan Insurance Corporation
限. Federal Trade Commission
力. Federal Works Administration, or Administrator
学. General Accounting Office
外. Comptroller General
调. General Services Administration
项. Department or Secretary of Health, Education and Welfare
北. Department or Secretary of Health and Human Services
工. Department or Secretary of Housing and Urban Development
笑. Interstate Commerce Commission
监. Indian Claims Commission
任. Immigration and Naturalization Service, or Director of, or District Director of, or Immigration and Naturalization Enforcement
相. Internal Revenue Service, Collector, Commissioner, or District Director of
微. Information Security Oversight Office
册. Department or Secretary of Labor
联. Loyalty Review Board
平. Legal Services Corporation
增. Merit Systems Protection Board
听. Multistate Tax Commission
解. National Aeronautics and Space Administration
等. Secretary or administrative unit of the U.S. Navy
得. National Credit Union Administration
收. National Endowment for the Arts
安. National Enforcement Commission
价. National Highway Traffic Safety Administration
藏. National Labor Relations Board, or regional office or officer
命. National Mediation Board
应. National Railroad Adjustment Board
看. Nuclear Regulatory Commission
索. National Security Agency
资. Office of Economic Opportunity
产. Office of Management and Budget
串. Office of Price Administration, or Price Administrator
布. Office of Personnel Management
原. Occupational Safety and Health Administration
知. Occupational Safety and Health Review Commission
级. Office of Workers' Compensation Programs
水. Patent Office, or Commissioner of, or Board of Appeals of
击. Pay Board (established under the Economic Stabilization Act of 1970)
好. Pension Benefit Guaranty Corporation
物. U.S. Public Health Service
放. Postal Rate Commission
亿. Provider Reimbursement Review Board
经. Renegotiation Board
模. Railroad Adjustment Board
之. Railroad Retirement Board
台. Subversive Activities Control Board
州. Small Business Administration
配. Securities and Exchange Commission
画. Social Security Administration or Commissioner
统. Selective Service System
共. Department or Secretary of the Treasury
连. Tennessee Valley Authority
海. United States Forest Service
节. United States Parole Commission
退. Postal Service and Post Office, or Postmaster General, or Postmaster
間. United States Sentencing Commission
比. Veterans' Administration
问. War Production Board
至. Wage Stabilization Board
备. General Land Office of Commissioners
你. Transportation Security Administration
黑. Surface Transportation Board
或. U.S. Shipping Board Emergency Fleet Corp.
与. Reconstruction Finance Corp.
影. Department or Secretary of Homeland Security
话. Unidentifiable
视. International Entity
Answer:

Answer: 标