Qui Tam & FCA Glossary
The world of qui tam litigation comes with its own vocabulary, much of it rooted in Latin and decades of case law. This glossary defines the terms you will encounter across QuitamOnline in plain English, so the rest of the site — and any conversation with an attorney — makes sense.
About This Glossary
Each entry provides a clear definition in plain English and links to related pages where you can learn more. These materials are for educational purposes only and do not constitute legal advice.
General information only, not legal advice, and current as of 2026. See our disclaimer.
Core Definitions
Qui Tam
A shortened form of a Latin phrase meaning roughly "he who sues for the king as well as for himself." It refers to a lawsuit brought by a private person on the government's behalf under the False Claims Act. In short: an insider sues a fraudster on behalf of the United States and shares in the recovery.
The qui tam mechanism is what allows private citizens to enforce a federal statute the government could not police on its own.
Relator
The relator is the whistleblower — the private individual who files the qui tam lawsuit. It is the person with first-hand knowledge of the fraud who steps forward as the named plaintiff, in partnership with the government, and is eligible for a share of any recovery.
In qui tam cases, "relator" and "whistleblower" refer to effectively the same person — relator is the formal legal term.
False Claims Act (FCA)
The federal statute, dating to 1863, that makes it illegal to knowingly submit false or fraudulent claims for government funds. It authorizes both government enforcement and private qui tam suits.
Penalties include treble damages and per-claim civil penalties. See our False Claims Act guide for a full overview.
Seal / Under Seal
When a qui tam complaint is filed under seal, it is kept confidential — hidden from the defendant and the public — while the government investigates.
The seal protects the investigation and the relator's identity during the early phase of the case. Our case timeline explains how long the seal period typically lasts.
Intervention
The government's decision to formally take over and lead a qui tam case after investigating it. If the government intervenes, it drives the litigation; if it declines, the relator may proceed alone.
Intervention strongly signals the case's merit and affects the relator's eventual share — see whistleblower rewards.
Materiality
A misrepresentation is material if it is capable of influencing the government's decision to pay a claim. Trivial or technical violations that would not affect payment generally are not material.
Materiality is a frequent point of dispute in modern FCA cases, particularly after the Supreme Court's decision in Universal Health Services v. United States ex rel. Escobar.
More Key Terms
Public Disclosure Bar
A rule that can block a qui tam claim if it is based on information already disclosed publicly — in the news, government reports, or court records — unless the relator qualifies as an original source.
Original Source
A relator who has independent knowledge that materially adds to publicly disclosed information, or who voluntarily disclosed the information to the government before it became public. Being an original source can overcome the public disclosure bar.
First-to-File Rule
The principle that only the first relator to file a qui tam action on a particular fraud can recover. Later filers on the same conduct are generally barred — see our eligibility guide.
Treble Damages
A penalty equal to three times the government's actual damages. Combined with per-claim civil penalties, treble damages make FCA exposure severe and drive most cases toward settlement.
Anti-Kickback Statute
A separate federal law prohibiting payment of anything of value to induce referrals of services covered by federal healthcare programs. Kickback-tainted claims can become false claims under the FCA.
Stark Law
A law restricting physicians from referring Medicare and Medicaid patients to entities with which they have a financial relationship, subject to exceptions. See our Stark Law case study.
Reverse False Claim
A claim based not on improperly obtaining money but on improperly avoiding an obligation to pay or return money owed to the government. Read more on our False Claims Act guide →
Frequently Asked Questions
What is the simplest definition of qui tam?
A lawsuit a private person files on the government's behalf against someone defrauding it, with a share of the recovery as the reward.
What is the difference between a relator and a whistleblower?
In qui tam cases they are effectively the same person — "relator" is the formal legal term for the whistleblower who files the suit.
What does "under seal" mean?
It means the case is filed confidentially so the government can investigate without alerting the defendant or the public.
Why does materiality matter so much?
Because a false statement only triggers liability if it could have affected the government's payment decision — minor technical violations usually do not qualify.
What is the first-to-file rule?
Only the first relator to file on a given fraud can recover, making prompt filing critical.
Explore Next
Continue with False Claims Act, Do I Have a Case?, or Whistleblower Rewards.
Current as of 2026