Patent Terms and Definitions

Definitions of common patent terms

By , Attorney

Abstract: a concise, one-paragraph summary of the patent. It details the structure, nature, and purpose of the invention. The abstract is used by the PTO and the public to quickly determine the gist of what is being disclosed.

Actual damages (also known as compensatory damages): in a lawsuit, money awarded to one party to cover actual injury or economic loss. Actual damages are intended to put the injured party in the position he was in prior to the injury.

Answer: a written response to a complaint (the opening papers in a lawsuit) in which the defendant admits or denies the allegations and may provide a list of defenses.

Best mode: the inventor's principal and preferred method of embodying the invention.

Board of Appeals and Patent Interferences (BAPI): a tribunal of judges at the PTO that hears appeals from final Office Actions.

Cease and desist letter: correspondence from the owner of a proprietary work, for example, a patent, copyright, trademark or trade secret, that requests the cessation of all infringing activity.

Clear and convincing proof: evidence that is highly probable and free from serious doubt.

Complaint: papers filed with a court clerk by the plaintiff to initiate a lawsuit by setting out facts and legal claims (usually called causes of action).

Compositions of matter: items such as chemical compositions, conglomerates, aggregates, or other chemically significant substances that are usually supplied in bulk (solid or particulate), liquid, or gaseous form.

Conception: the mental part of inventing, including how an invention is formulated or how a problem is solved.

Confidentiality agreement: (also known as a nondisclosure agreement) a contract in which one or both parties agree not to disclose certain information.

Continuation application: a new patent application that allows the applicant to re-present an invention and get a second or third bite at the apple. The applicant can file a new application (known as a "continuation") while the original (or "parent") application is still pending. A continuation application consists of the same invention, cross-referenced to the parent application and a new set of claims. The applicant retains the filing date of the parent application for purposes of determining the relevancy of prior art.

Continuation-in-Part (CIP): less common than a continuation application, this form of extension application is used when a portion or all of an earlier patent application is continued and new matter (not disclosed in the earlier application) is included. CIP applications are used when an applicant wants to present an improvement but is prevented from adding a pending application to it because of the prohibition against adding "new matter."

Continuing Prosecution Application (CPA): a patent application that is like a continuation application in effect, but no new application need be filed. The applicant merely pays another filing fee, submits new claims, and files a CPA request form. CPAs can only be used for applications filed prior to 2000 May 29. Applications after that date must use the Request for Continued Examination.

Contributory infringement: occurs when a material component of a patented invention is sold with knowledge that the component is designed for an unauthorized use. This type of infringement cannot occur unless there is a direct infringement. In other words, it is not enough to sell infringing parts; those parts must be used in an infringing invention.

Copyright: the legal right to exclude others, for a limited time, from copying, selling, performing, displaying, or making derivative versions of a work of authorship such as a writing, music, or artwork.

Counterclaim: a legal claim usually asserted by the defendant against an opposing party, usually the plaintiff.

Court of Appeals for the Federal Circuit (CAFC): the federal appeals court that specializes in patent appeals. If the Board of Appeals and Patent Interferences rejects an application appeal, an applicant can further appeal to the CAFC within 60 days of the decision. If the CAFC upholds the PTO, the applicant can request the United States Supreme Court hear the case (although the Supreme Court rarely hears patent appeals).

Declaratory relief: a request that the court sort out the rights and legal obligations of the parties in the midst of an actual controversy.

Deposit date: the date the PTO receives a patent application.

Deposition: oral or written testimony of a party or witness and given under oath.

Design patent: covers the unique, ornamental, or visible shape or design of a non-natural object.

Divisional application: a patent application used when an applicant wants to protect several inventions claimed in the original application. The official definition is "a later application for a distinct or independent invention, carved out of a pending application and disclosing and claiming only subject matter disclosed in the earlier or parent application" (MPEP 201.06). A divisional application is entitled to the filing date of the parent case for purposes of overcoming prior art. The divisional application must be filed while the parent is pending. A divisional application can be filed as a CPA.

Doctrine of Equivalents (DoE): a form of patent infringement that occurs when an invention performs substantially the same function in substantially the same manner and obtains the same result as the patented invention. A court analyzes each element of the patented invention separately. Under a recent Supreme Court decision, the DoE must be applied on an element-by-element basis to the claims.

Double patenting: when an applicant has obtained a patent and has filed a second application containing the same invention, the second application will be rejected. If the second application resulted in a patent, that patent will be invalidated. Two applications contain the same invention when the two inventions are literally the same or the second invention is an obvious modification of the first invention.

Enhanced damages (treble damages): in exceptional infringement cases, financial damages may be increased, at the discretion of the court, up to triple the award for actual damages (known as "enhanced damages").

Exclusive jurisdiction: the sole authority of a court to hear a certain type of case.

Exhaustion: (see "first sale doctrine").

Ex parte: (Latin: one party only) refers to legal proceedings where only one party is present or represented.

File wrapper estoppel: (or prosecution history estoppel) affirmative defense used in patent infringement litigation that precludes the patent owner from asserting rights that were disclaimed during the patent application process. The term is derived from the fact that the official file in which a patent is contained at the Patent and Trademark Office is known as a "file wrapper." All statements, admissions, correspondence, or documentation relating to the invention are placed in the file wrapper. Estoppel means that a party is prevented from acting contrary to a former statement or action when someone else has relied to his detriment on the prior statement or action.

Final office action: the examiner's response to the applicant's first amendment, The final Office Action is supposed to end the prosecution stage but a "final action" is rarely final.

First office action: (sometimes called an "official letter" or "OA") response from the patent examiner after the initial examination of the application. It is very rare that an application is allowed in the first Office Action. More often, the examiner rejects some or all of the claims.

First sale doctrine: (also known as the exhaustion doctrine) once a patented product (or product resulting from a patented process) is sold or licensed, the patent owner's rights are exhausted and the owner has no further rights as to the resale of that particular article.

Generic (genus): an entire group or class, or a group of related items or species.

Grace period: a period in which an action may be taken even though the normal period for taking action has passed.

Indirect infringement: occurs either when someone is persuaded to make, use, or sell a patented invention without authorization (inducing infringement); or when a material component of a patented invention is sold with knowledge that the component is designed for an unauthorized use (contributory infringement). An indirect infringement cannot occur unless there is a direct infringement. In other words, it is not enough to sell infringing parts; those parts must be used in an infringing invention.

Infringement: an invention is infringing if it is a literal copy of a patented invention or if it performs substantially the same function in substantially the same manner and obtains the same result as the patented invention (see "doctrine of equivalents").

Injunction: a court order requiring that a party halt a particular activity. In the case of patent infringement, a court can order all infringing activity be halted at the end of a trial (a permanent injunction) or the patent owner can attempt to halt the infringing activity immediately, rather than wait for a trial (a preliminary injunction). A court uses two factors to determine whether to grant a preliminary injunction: (1) Is the plaintiff likely to succeed in the lawsuit? and (2) Will the plaintiff suffer irreparable harm if the injunction is not granted? The patent owner may seek relief for a very short injunction known as a temporary restraining order or TRO, which usually only lasts a few days or weeks. A temporary restraining order may be granted without notice to the infringer if it appears that immediate damage will result—for example, that evidence will be destroyed.

Interference: a costly, complex PTO proceeding that determines who will get a patent when two or more applicants are claiming the same invention. It is basically a method of sorting out priority of inventorship. Occasionally an interference may involve a patent that has been in force for less than one year.

Inter partes: (Latin: between parties) refers to legal proceedings where all parties to the action are represented.

Interrogatories: written questions that must be answered under oath.

Invention: any new article, machine, composition, or process or new use developed by a human.

Jury instructions: explanations of the legal rules that the jury must use in reaching a verdict.

Lab notebook: a system of documenting an invention that usually includes descriptions of the invention and novel features; procedures used in the building and testing of the invention; drawings, photos, or sketches of the invention; test results and conclusions; discussions of any known prior-art references; and additional documentation such as correspondence and purchase receipts.

Literal infringement: occurs if a defendant makes, sells, or uses the invention defined in the plaintiff's patent claim. In other words, the infringing product includes each and every component, part, or step in the patented invention. It is a literal infringement because the defendant's device is actually the same invention in the patent claim.

Machine: a device or things used for accomplishing a task; usually involves some activity or motion performed by working parts.

Magistrate: an officer of the court, who may exercise some of the authority of a federal district court judge, including the authority to conduct a jury or non-jury trial.

Manufactures: (sometimes termed "articles of manufacture") items that have been made by human hands or by machines; may have working or moving parts as prime features.

Means-plus-function clause (or means for clause): a provision in a patent claim in which the applicant does not specifically describe the structure of one of the items in the patent and instead describes the function of the item. Term is derived from the fact that the clause usually starts with the word "means."

Micro entity: individual applicant who, based on income and previously filed patents, qualifies as a micro-entity and pays the lowest USPTO fees (approximately one-quarter of regular fees, and one-half of small entity fees).

New matter: any technical information, including dimensions, materials, etc., that was not present in the patent application as originally filed. An applicant can never add new matter to an application (PTO Rule 118).

New-use invention: a new and unobvious process or method for using an old and known invention.

Nonobviousness: a standard of patentability that requires that an invention produce "unusual and surprising results." In 1966, the U.S. Supreme Court established the steps for determining unobviousness in the case of Graham v. John Deere, 383 U.S. 1 (1966).

Notice of Allowance: a document issued when the examiner is convinced that the application meets the requirements of patentability. An issue fee is due within three months.

Objects and advantages: a phrase used to explain "what the invention accomplishes." Usually, the objects are also the invention's advantages, since those aspects are intended to be superior over prior art.

Office Action (OA, also known as Official Letter or Examiner's Action): correspondence (usually including forms and a letter) from a patent examiner that describes what is wrong with the application and why it cannot be allowed. Generally, an OA will reject claims, list defects in the specifications or drawings, raise objections, or cite and enclose copies of relevant prior art demonstrating a lack of novelty or nonobviousness.

Patent: a grant from a government that confers upon an inventor the right to exclude others from making, using, selling, importing, or offering an invention for sale for a fixed period of time.

Patent application: a set of papers that describe an invention and that are suitable for filing in a patent office in order to apply for a patent on the invention.

Patent Application Declaration (PAD): an attestation by the applicant that the inventor understands the contents of the claims and specification and has fully disclosed all material information. The PTO provides a form for the PAD.

Patent misuse: a defense in patent infringement that prevents a patent owner who has abused patent law from enforcing patent rights. Common examples of misuse are violation of the antitrust laws or unethical business practices.

Patent pending: (also known as the "pendency period") time between filing a patent application (or PPA) and issuance of the patent. The inventor has no patent rights during this period. However, when and if the patent later issues, the inventor will obtain the right to prevent the continuation of any infringing activity that started during the pendency period. If the application has been published by the PTO during the pendency period and the infringer had notice, the applicant may later seek royalties for these infringements during the pendency period. It's a criminal offense to use the words "patent applied for" or "patent pending" (they mean the same thing) in any advertising if there's no active, applicable regular or provisional patent application on file.

Patent prosecution: the process of shepherding a patent application through the Patent and Trademark Office.

Patent Rules of Practice: administrative regulations located in Volume 37 of the Code of Federal Regulations (37 C.F.R. § 1).

Pendency period: (see patent pending).

Permanent injunction: a durable injunction issued after a final judgment on the merits of the case; permanently restrains the defendant from engaging in the infringing activity.

Petition to Make Special: an applicant can, under certain circumstances, have an application examined sooner than the normal course of PTO examination (one to three years). This is accomplished by filing a "Petition to Make Special" (PTMS), together with a Supporting Declaration.

Plant patent: covers plants that can be reproduced through the use of grafts and cuttings (asexual reproduction).

Power of attorney: a document that gives another person legal authority to act on your behalf. If an attorney is preparing an application on behalf of an inventor, a power of attorney should be executed to authorize the patent attorney or agent to act on behalf of the inventor. The power of attorney form may be combined with the PAD.

Prima facie: (Latin: on its face) at first sight, obvious.

Prior art: the state of knowledge existing or publicly available before the date of filing of the patent application.

Process: (sometimes referred to as a "method") a way of doing or making things that involves more than purely mental manipulations.

Provisional Patent Application (PPA): an interim document that clearly explains how to make and use the invention. The PPA is equivalent to a reduction to practice (see below). If a regular patent application is filed within one year of filing the PPA, the inventor can use the PPA's filing date for the purpose of deciding whether a reference is prior art. In addition to an early filing date, an inventor may claim patent pending status for the one-year period following the filing of the PPA.

Reissue application: an application used to correct information in a patent. It is usually filed when a patent owner believes the claims are not broad enough, the claims are too broad (the applicant discovered a new reference), or there are significant errors in the specification. In these cases, the applicant seeks to correct the patent by filing an application to get the applicant's original patent reissued at any time during its term. The reissue patent will take the place of the applicant's original patent and expire the same time as the original patent would have expired. If the applicant wants to broaden the claims of the patent through a reissue application, the applicant must do so within two years from the date the original patent issued. There is a risk in filing a reissue application because all of the claims of the original patent will be examined and can be rejected.

Repair doctrine: affirmative defense based on the right of an authorized licensor of a patented device to repair and replace unpatented components. It also includes the right to sell materials used to repair or replace a patented invention The defense does not apply for completely rebuilt inventions, unauthorized inventions, or items that are made or sold without authorization of the patent owner.

Request for admission: request for a party to the lawsuit to admit the truthfulness of a statement.

Request for Continued Examination (RCE): a paper filed when a patent applicant wishes to continue prosecuting an application that has received a final Office Action. Filing the RCE with another filing fee effectively removes the final action so that the applicant can submit further amendments, for example, new claims, new arguments, a new declaration, or new references.

Request for production of documents: the way a party to a lawsuit obtains documents or other physical evidence from the other side.

Reverse doctrine of equivalents (or negative doctrine of equivalents): a rarely used affirmative defense to patent infringement in which, even if there is a literal infringement, the court will excuse the defendant's conduct if the infringing device has a different function or result than the patented invention. The doctrine is applied when the allegedly infringing device performs the same function in a substantially different way.

Sequence listing: an attachment to a patent application used if a biotech invention includes a sequence listing of a nucleotide or amino acid sequence. The applicant attaches this information on separate sheets of paper and refers to the sequence listing in the application (see PTO Rule 77). If there is no sequence listing, the applicant states "Nonapplicable."

Small entity: a status that enables small businesses, independent inventors, and nonprofit companies to pay a reduced application fee. There are three types of small entities: (1) independent inventors, (2) nonprofit companies, and (3) small businesses. To qualify, an independent inventor must either own all rights, or have transferred—or be obligated to transfer—rights to a small business or nonprofit organization. Nonprofit organizations are defined and listed in the Code of Federal Regulations and usually are educational institutions or charitable organizations. A small-entity business is one with fewer than 500 employees. The number of employees is computed by averaging the number of full- and part-time employees during a fiscal year.

Species: one of a group of related individual items collectively subordinate to a genus.

Specification: a patent application disclosure made by the inventor and drafted so that an individual skilled in the art to which the invention pertains could, when reading the patent, make and use the invention without needing further experiment. A specification is constructed of several sections. Collectively, these sections form a narrative that describes and distinguishes the invention. If it can later be proved that the inventor knew of a better way (or "best mode") and failed to disclose it, that failure could result in the loss of patent rights.

Statute of limitations: the legally prescribed time limit in which a lawsuit must be filed. In patent law there is no time limit (statute of limitations) for filing a patent infringement lawsuit, but monetary damages can only be recovered for infringements committed during the six years prior to the filing the lawsuit. For example, if a patent owner sues after ten years of infringement, the owner cannot recover monetary damages for the first four years of infringement. Despite the fact that there is no law setting a time limit, courts will not permit a patent owner to sue for infringement if the owner has waited an unreasonable time to file the lawsuit ("laches").

Statutory Invention Registration (SIR): a document that allows an applicant who abandons an application to prevent anyone else from getting a valid patent on the same invention. This is accomplished by converting the patent application to a SIR.

Statutory subject matter: an invention that falls into one of the five statutory classes: process (method), machine, article of manufacture, composition, or a "new use" of one of the first four.

Substitute application: essentially a duplicate of an abandoned patent application. (See MPEP § 201.09.) The disadvantage of a substitute application is that the applicant doesn't get the benefit of the filing date of the previously abandoned patent application, which could be useful, because any prior art occurring after the filing date of the earlier case can be used against the substitute case. If the applicant's substitute application issues into a patent, the patent will expire 20 years from the filing date of the substitute.

Successor liability: responsibility for infringement that is borne by a company that has purchased another company that is liable for infringements. In order for successor liability to occur, there must be an agreement between the companies to assume liability, a merger between the companies, or the purchaser must be a "continuation" of the purchased business. If the sale is made to escape liability and lacks any of the foregoing characteristics, liability will still attach.

Summons: a document served with the complaint that tells the defendant he has been sued, has a certain time limit in which to respond, and must appear in court on a stated date.

Temporary restraining order (TRO): a court order that tells one party to do or stop doing something—for example to stop infringing. A TRO is issued after the aggrieved party appears before a judge. Once the TRO is issued, the court holds a second hearing where the other side can tell his story and the court can decide whether to make the TRO permanent by issuing an injunction. The TRO is often granted ex parte (without allowing the other side to respond), and for that reason is short in duration and only remains in effect until the court has an opportunity to schedule a hearing for the preliminary injunction.

Traverse: to argue against.

Tying: a form of patent misuse in which, as a condition of a transaction, the buyer of a patented device must also purchase an additional product. For example, in one case a company had a patent on a machine that deposited salt tablets in canned food. Purchasers of the machine were also required to buy salt tablets from the patent owner. A party that commits patent misuse may have its patent invalidated, may have to pay monetary damages, or both.

Utility patent: the main type of patent, which covers inventions that function in a unique manner to produce a utilitarian result.

verified statement a statement made under oath or a declaration. A false verified statement is punishable as perjury.

Vicarious liability: legal responsibility that results when a business such as a corporation or partnership is liable for infringements committed by employees or agents. This liability attaches when the agent acts under the authority or direction of the business, an employee acts within the scope of employment, or the business benefits from, or adopts or approves the infringing activity.

Voir dire ("speak the truth"): process by which attorneys and judges question potential jurors in order to determine whether they may be fair and impartial.

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