The catch log
Everyone's panicking about AI hallucinations.
Here's what the errors actually were.
Real errors we caught in real briefs — the case exists, the citation looks right, and it's still wrong. Each one tagged with our best read on where it came from. “Likely” is a judgment, not a certainty.
18
errors caught
61%
were NOT AI hallucinations
11 / 4 / 3
likely human / unclear / likely AI
| Case | What was wrong | Verdict | Reason |
|---|---|---|---|
Wilton v. Seven Falls Co. 515 U.S. 277 | Citation error A brief cited Wilton v. Seven Falls Co., 515 U.S. 277, 286–87 (1995) for the proposition that a district court may dismiss a declaratory judgment claim that "merely restates the defense to the plaintiff's own affirmative claims."
Wilton holds that Brillhart discretion governs a federal declaratory action when parallel state proceedings are pending. Its subject is the relationship between two courts, not redundancy between counts in one complaint.
The court that sanctioned this brief listed this citation twice, finding it "does not stand for the proposition." | Partial support | Likely AI |
Streetwise Maps, Inc. v. VanDam, Inc. 159 F.3d 739 | Overstates the holding A trademark brief stated that a conceptually weak mark "is entitled only to narrow protection against materially different overall commercial impressions," citing Streetwise Maps, Inc. v. VanDam, Inc., 159 F.3d 739, 744 (2d Cir. 1998). At 744 the Second Circuit wrote that a mark weakened by third-party use "should not receive the fullest protection available under the law … unless a convincing combination of other Polaroid factors militates strongly in favor of finding that a likelihood of confusion exists." That is one factor in a rebuttable balancing test, and the qualifying clause is what makes it rebuttable. The brief restates it as a rule and drops the condition — then the next sentence calls the differences between the marks "legally dispositive under Streetwise," which is what the opinion says they are not. The citation and the page are correct; the omitted clause is the finding. | Partial support | Unclear |
O Zon Inc. v. Charles 272 F. Supp. 2d 307 | Wrong pincite A trademark brief cited O Zon Inc. v. Charles, 272 F. Supp. 2d 307, 317–18 (S.D.N.Y. 2003). The opinion runs from 307 to 314. There are no pages 317–18 in that case.
The proposition itself is sound — at 313 the court faults plaintiffs for never alleging "what makes its restaurant so distinctive" — so the citation fails on the page, not the substance.
The court that sanctioned this brief listed this citation twice, noting the case ends at 314. | Partial support | Likely AI |
Streetwise Maps, Inc. v. VanDam, Inc. 159 F.3d 739 | Overstates the holding A trademark brief cited Streetwise Maps, Inc. v. VanDam, Inc., 159 F.3d 739, 743–44 (2d Cir. 1998) as "strongly suggest[ing]" that the plaintiff's own mark "derived whatever distinctiveness it possessed from its unusual construction," and distinguished the defendant's mark as communicating "a different idea in a different sequence." Across the full opinion the words "unusual," "construction," "coined," and "sequence" appear zero times. The Second Circuit ranked the mark "suggestive for its inherent distinctiveness" while holding it "not strong in the marketplace for maps," and attributed its weakness to third-party use of the words "street" and "wise" — the shared elements reduced the mark's strength rather than supplying it. The court's dissimilarity holding rests on visual presentation: the marks are "not confusingly similar, given the context in which a purchaser sees them," because the defendant's mark occupies "one-twelfth of the cover" while "Streetwise" appears with "Manhattan" across "one-third of the cover's space." Its supporting citations are presentation cases — a six-digit model number in Arrow Fastener, "a different typeface" in W.W.W. Pharmacal and in Lang. The quoted language is accurate and on the cited page. The rationale the brief draws from it — that word construction and sequence determine distinctiveness — is not in the case. | Partial support | Unclear |
Streetwise Maps, Inc. v. VanDam, Inc. 159 F.3d 739 | Citation error A trademark brief cited Streetwise Maps, Inc. v. VanDam, Inc., 159 F.3d 739, 744 (2d Cir. 1998) for the proposition that plaintiffs "must instead plead similarity sufficient to make confusion plausible notwithstanding the weakness of the shared elements." Streetwise was decided after a bench trial: "After a bench trial, Judge Chin, in an oral decision rendered on June 25, 1997, dismissed Streetwise's complaint in its entirety with prejudice." Across the full opinion, "plead" appears 0 times, "pleading" 0, and "motion to dismiss" 0. The cited page does support the narrower point the brief builds on — third-party use of the words "street" and "wise" weakens the mark, which "should not receive the fullest protection available under the law." What the case does not supply is a pleading standard. It was offered on a motion to dismiss for what a complaint must contain, drawn from a decision reached on a full trial record. | Partial support | Unclear |
Polaroid Corp. v. Polarad Elecs. Corp. 287 F.2d 492 | Overstates the holding A trademark brief stated that "the threshold inquiry in any likelihood-of-confusion analysis is the strength of the senior mark," citing Polaroid Corp. v. Polarad Electronics Corp., 287 F.2d 492, 495 (2d Cir. 1961).
At 495 the Second Circuit wrote that "the prior owner's chance of success is a function of many variables: the strength of his mark, the degree of similarity between the two marks, the proximity of the products…" — the passage that gives the Polaroid factors their name. Strength is the first of several coequal variables, not a threshold that decides whether the rest are reached. | Partial support | Likely human |
Sulzer Mixpac AG v. A&N Trading Co. 988 F.3d 174 | Citation error A trademark brief cited Sulzer Mixpac AG v. A&N Trading Co., 988 F.3d 174, 181 (2d Cir. 2021) for the proposition that "trade dress claims may be dismissed where the asserted dress is functional as a matter of law or where the complaint fails to allege facts sufficient to establish distinctiveness."
Sulzer Mixpac was decided on appeal from a bench trial, holding color-coded mixing tips functional under the Louboutin/Inwood test. The phrase "bench trial" appears seven times in the opinion; "motion to dismiss" does not appear at all. The case supports the functionality point on a full record. It decides nothing about what a complaint must allege. | Partial support | Unclear |
TrafFix Devices, Inc. v. Mktg. Displays, Inc. 532 U.S. 23 | Overstates the holding A trademark brief cited TrafFix Devices, Inc. v. Marketing Displays, Inc., 532 U.S. 23, 29–30 (2001) for the proposition that "courts are especially reluctant to extend trade-dress protection to methods of service delivery, because doing so gives one competitor exclusive rights over a manner of doing business."
TrafFix concerns functional product design — a dual-spring mechanism on a road sign stand, following an expired utility patent. Its holding is that functional features cannot be protected as trade dress. It does not address methods of service delivery, and expresses no heightened reluctance about them.
The quotation is accurate and on the cited page. The functionality doctrine it states is real. What the brief adds is the category the doctrine is applied to. | Partial support | Likely human |
Brennan's, Inc. v. Brennan's Rest., LLC 360 F.3d 125 | Overstates the holding A trademark brief stated that Brennan's, Inc. v. Brennan's Restaurant, LLC, 360 F.3d 125, 132 (2d Cir. 2004) "held that a mark built from commonly used matter in the restaurant field received only restricted protection."
At 132 the Second Circuit held: "As a common last name … plaintiff's mark is inherently weak…. A common last name implicates both the minimal level of protection traditionally granted to descriptive marks."
The holding rests on the common-surname doctrine. Brennan's is a restaurant case, which makes "in the restaurant field" read as accurate — but the court's rule is about surnames, not about ordinary words of the trade. The brief cited it to argue that two common restaurant words yield narrow protection, which is not what the case decided. | Partial support | Likely human |
Streetwise Maps, Inc. v. VanDam, Inc. 159 F.3d 739 | Citation error A trademark brief cited Streetwise Maps, Inc. v. VanDam, Inc., 159 F.3d 739, 744 (2d Cir. 1998) for the proposition that incontestability "bars certain validity challenges, but … does not convert a conceptually weak mark into a strong one or expand the scope of protection against nonidentical marks."
Streetwise is a likelihood-of-confusion case. It analyzes marketplace strength and third-party use under the Polaroid factors. It does not discuss incontestability, §1065, or what incontestable status does to the scope of protection.
The co-cited case in the same sentence does support the clause it was offered for; only this citation was flagged.
The court that sanctioned this brief reached the same conclusion independently: "Mischaracterization of the law. Streetwise does not address incontestability." | Partial support | Likely AI |
Bethune-Hill v. Va. State Bd. of Elections 580 U.S. 178 | Holding inverted (opposite) "Breathing room" is genuine majority language used to
PROTECT legislatures' latitude (rejecting a rule affording "too little breathing room"); the brief inverts it to argue
the doctrine "suffocates" them. | Partial support | Likely human |
In re Landry 83 F.4th 300 | Overstates the holding Mandamus did vacate the district court's remedial
hearing, but the "five legislative day" deadline the brief pins it to belongs to the 2022 proceeding (Robinson v.
Ardoin, 37 F.4th 208), not the 2023 mandamus over the rushed October hearing. | Partial support | Likely human |
Rodriguez de Quijas v. Shearson/American Express, Inc. 490 U.S. 477 | Overstates the holding "Steadily eroded" / "outmoded presumption" are real but describe judicial hostility to arbitration, not a
general "outmoded interpretive methodology" — repurposed out of context. | Partial support | Likely human |
Northwest Austin Mun. Utility Dist. No. One v. Holder 557 U.S. 193 | Misattribution The "current burdens / current needs" quote is genuine majority language but refers to the Act's
preclearance regime (Section 5); the brief attributes it to Section 2. | Partial support | Likely human |
City of Rome v. United States 446 U.S. 156 | Overstates the holding Quotes are accurate, but the brief recasts a sufficient rational basis ("risk of purposeful
discrimination") as a necessary limitation ("only where") — overreads the holding. | Partial support | Likely human |
Students for Fair Admissions, Inc. v. President & Fellows of Harv. Coll. 600 U.S. 181 | Overstates the holding Invoked analogically for voting conditions, but the case addresses equal-protection limits on race-based
admissions and does not reach the Voting Rights Act. | Partial support | Likely human |
Shelby County v. Holder 570 U.S. 529 | Overstates the holding Cited for the idea that current conditions can't justify excessive consideration of race, but the case
concerns the VRA coverage formula and federalism, not race-conscious districting — only tangential support. | Partial support | Likely human |
United States v. Reese 92 U.S. 214 | Dissent quoted as holding Quoted a dissent as the Court's holding — the majority actually narrowed the Fifteenth Amendment and struck down the
statute the quote was used to support. | Does not support | Likely human |
Cases are public record. Brief content is never shown — each entry is de-identified, and the origin label is our hedged judgment, not a determination about any author.
