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What is behind Lexxington

A knowledge base built from official sources, an ontology that links the syllabus with rules, decisions and exercises, and an AI tutor that names its sources. This page explains how it fits together and how far it has come.

From syllabus to exercise, linked

  1. Exam rulesWhat your jurisdiction tests
  2. Subject and topicHow the material is structured
  3. RuleThe provision in its wording
  4. DecisionHow courts apply the rule
  5. Lesson, card, question, caseHow you practise the topic
  6. Your progressWhat holds and where there is a gap

Knowledge base

How the knowledge base learns

Internally it is called Krake. Everything is a node in a network: exam rules and curricula lead to subjects, subjects to rules, rules to decisions, decisions to cases, questions and cards. Every answer you give flows back into the network as a signal.

Exam rulesCurriculumObligationsCriminal lawEvidence§ 433 BGBArt. 41 ORs 1 Theft Act 1968FRE 803BGH decisionLeading caseDecisionCase: defective goodsQuestionFlashcardYour progress

The training loop

Where the network lacks exercises for an exam topic, new material is written. Every task is graded separately, every citation checked against the knowledge base, and only then approved. A fixed set of test questions measures whether it gets better.

  1. 1gap found
  2. 2task written
  3. 3independently checked
  4. 4citation checked
  5. 5approved
  6. 6measurably better
88 %
substantively correct
80 %
main rule cited
76 %
rules found

First evaluation run, 25 test questions, as of 5 November 2026. Measured on Lexxi’s answers to fixed test questions; the figures rise or fall with every run.

In developmentLX1

Our own legal language model, trained on the knowledge base and the checked study content. Not in the app yet.

The knowledge base

Statutes and court decisions come from official sources, with version and origin. Internally this part is called Krake. The state per country:

  • GermanyStatutes: Federal law (gesetze-im-internet.de); state law of Bavaria, Brandenburg, Saxony, North Rhine-Westphalia; more states in progress (running). Decisions: Federal courts (rechtsprechung-im-internet.de), imported daily (running).
  • SwitzerlandStatutes: Federal law from Fedlex (in progress). Decisions: BGE and Federal Supreme Court (in progress).
  • United StatesStatutes: United States Code, CFR, Federal Rules (govinfo.gov) (in progress). Decisions: Decisions via CourtListener, in progress (in progress).
  • England and WalesStatutes: planned. Decisions: planned.

Germany, as of 5 November 2026: more than 100,000 provisions and more than 15,000 reviewed federal decisions. More under data coverage.

Exam rules and curricula

So the app knows what your exam covers, we read in the official exam rules and curricula, with version, period of validity and source.

  • Germany17 exam rule sets, 1 faculty curriculum
  • United States7 exam rule sets, 7 faculty curricula
  • United Kingdom2 exam rule sets, 4 faculty curricula
  • Switzerland9 exam rule sets, 7 faculty curricula

Counted from the documents we have read in. More follow.

The ontology

Everything in the app is a node in a network: exams, subjects, topics, rules, decisions, lessons, cards, questions and cases. The links say what belongs together. That is how the app can show the cases for a rule and tell you which topic of your exam you have not practised yet.

  • Rules and decisionsmore than 10,000 rules and more than 11,000 decisions are linked to the study material.
  • Exercisesmore than 20,000 cases, more than 8,000 questions, more than 4,500 cards and more than 3,000 lessons.
  • Linksmore than 180,000 links, such as “decision applies rule” or “question practises topic”.

All courses together, network as of 5 November 2026.

Lexxi, the AI tutor

Lexxi answers questions about the material on the basis of the course content and the knowledge base, and names the rules and decisions the answer relies on. So you see not just an answer but where it comes from.

Lexxi can be wrong, like any AI system. That is why it shows sources: check them. Lexxi is a study aid, not legal advice.

How you learn with it

  • Unlock step by stepLessons are split into sections. Each section sits behind a card: say it yourself first, then reveal. The learning path leads you on subject by subject.
  • Spaced reviewCards and questions come back on a schedule: what holds comes back later, what is shaky sooner.
  • Rules with case lawFrom the rule to the cases and decisions that apply it, and back.
  • Timed practiceYour own answer against the clock, graded by structure, then the model answer.
  • Progress and gapsBecause the app knows which topics belong to your exam, it shows you where you have not practised yet.

All features, the studies behind them.

The current state in numbers

CountryCasesQuestionsCardsLessons
Germanymore than 12,000more than 5,000more than 2,500more than 500
United Statesmore than 5,000more than 5,000more than 2,000more than 400
United Kingdommore than 1,100more than 2,500more than 1,100more than 160
Switzerlandmore than 1,100more than 1,400more than 45072

Counted from the course files when the page is built and rounded down. A case used in several courses counts once per country.

Frequently asked questions

Where do the statutes in Lexxington come from?

From official sources, such as gesetze-im-internet.de for German federal law. For Switzerland, the USA and the United Kingdom the import is being built; this page shows the state of each source.

What is the ontology?

A network of links: which exam requires which subject, which rule belongs to which topic, which decision applies which rule, and which question or case practises which topic. That is how the app knows what belongs together and where you still have gaps.

Can Lexxi invent rules?

Lexxi names the rules an answer relies on so you can check them. Like any AI system, Lexxi can be wrong. Lexxington is study material, not legal advice.

Are the figures on this page current?

They are counted from the course files and the data snapshot when the page is built, and rounded down. The German statute and decision snapshot is as of 5 November 2026.

Is everything complete?

No. The knowledge base keeps growing. What is still missing is marked as in progress or planned.

Lexxington for iPhone and iPad

Download it on the App Store. All content is included in the subscription in the app.

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Facts and figures

Study content counted from the course files on every release, the knowledge base hourly from our pipeline. All figures rounded down. Knowledge base as of 5 November 2026.

770,000+
legal documents in the knowledge base
2,300,000+
text segments, linked by our own pipeline
19,000+
cases
15,000+
questions
6,000+
flashcards
1,100+
lessons
350+
leading cases
59
faculty curricula
35
exam rules and syllabi
Germany
  • over 340,000 documents, incl. over 110,000 decisions
  • 107 statutes in the app library
  • 12,000+ cases, 5,000+ questions
  • 16 states
United States
  • over 320,000 documents, incl. over 4,800 decisions
  • 34 statutes in the app library
  • 5,000+ cases, 5,000+ questions
  • 56 jurisdictions
Switzerland
  • over 94,000 documents, incl. over 4,800 decisions
  • 12 statutes in the app library
  • 1,100+ cases, 1,400+ questions
  • 26 cantons
United Kingdom
  • over 19,000 documents, incl. over 940 decisions
  • 31 statutes in the app library
  • 1,100+ cases, 2,500+ questions

How we check the content

Content is written and reviewed in a multi-step process with source checks. Our training loop:

  1. 1
    Find gaps

    Where are questions, cards or cases missing for an exam topic?

  2. 2
    Write tasks

    Each gap gets new material, with the rule and its source.

  3. 3
    Independent review

    A second, separate check grades each task.

  4. 4
    Review queue

    Anything that does not clearly pass waits for approval instead of going live.

Legal review by subject-matter authors is being set up (planned).

  • Citation checker

    Checks that every cited rule and decision exists in the knowledge base.

  • Gold set

    A fixed set of checked questions and answers as the benchmark.

  • Nightly evaluation

    Every night Lexxi and the content run against the gold set, so regressions show up.

  • Second review

    Sensitive items pass a second review before they appear.

What we are working on

Not in the app yet. Labelled clearly, so nothing is promised that does not exist.

  • In developmentLX1, our own legal language model

    Trained on our own knowledge base and checked study content.

  • PlannedMore countries

    The knowledge base grows beyond the four markets; new courses follow once material and checks are in place.

  • PlannedTools for practice

    Later, sourced research for working lawyers too, on the same knowledge base.

Built on the official exam rules and curricula

The content follows the exam rules of each German state and the curricula of 41 German law faculties, plus the rules in Switzerland, the United Kingdom and the US.

Law faculties in Germany (41)

  • Albert-Ludwigs-Universität Freiburg
  • Bucerius Law School – Hochschule für Rechtswissenschaft
  • Christian-Albrechts-Universität zu Kiel
  • Eberhard Karls Universität Tübingen
  • EBS Universität für Wirtschaft und Recht
  • Europa-Universität Viadrina Frankfurt (Oder)
  • FernUniversität in Hagen
  • Freie Universität Berlin
  • Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)
  • Friedrich-Schiller-Universität Jena
  • Georg-August-Universität Göttingen
  • Gottfried Wilhelm Leibniz Universität Hannover
  • Heinrich-Heine-Universität Düsseldorf
  • Humboldt-Universität zu Berlin
  • Johann Wolfgang Goethe-Universität Frankfurt am Main
  • Johannes Gutenberg-Universität Mainz
  • Julius-Maximilians-Universität Würzburg
  • Justus-Liebig-Universität Gießen
  • Ludwig-Maximilians-Universität München
  • Martin-Luther-Universität Halle-Wittenberg
  • Philipps-Universität Marburg
  • Rheinische Friedrich-Wilhelms-Universität Bonn
  • Ruhr-Universität Bochum
  • Universität Augsburg
  • Universität Bayreuth
  • Universität Bielefeld
  • Universität Bremen
  • Universität des Saarlandes
  • Universität Greifswald
  • Universität Hamburg
  • Universität Heidelberg
  • Universität Konstanz
  • Universität Leipzig
  • Universität Mannheim
  • Universität Münster
  • Universität Osnabrück
  • Universität Passau
  • Universität Potsdam
  • Universität Regensburg
  • Universität Trier
  • Universität zu Köln

Exam rules in Germany (17)

  • Brandenburg§ 3 Abs. 2 und § 7 BbgJAG i.V.m. § 3 BbgJAO (R = vertieft, G = Grundzüge)
  • BerlinBerliner JAG §§ 6 ff. i.V.m. JAO (Berliner Juristenausbildungsordnung vom 04.08.2003), Prüfungsstoff in § 3 JAO
  • Baden-Württemberg§ 8 JAPrO vom 02.05.2019 (GBl. 2019 S. 131)
  • Bayern§ 18 JAPO (Ausbildungs- und Prüfungsordnung für Juristen vom 13.10.2003, BayRS 2038-3-3-11-J)
  • Deutschland (Bund)§ 5a DRiG (Studium), § 5d DRiG (Prüfungen)
  • BremenBis 31.03.2023: § 5 JAPG a.F.; ab 01.04.2023: §§ 7, 14 Abs. 3 JAPG i.V.m. Prüfungsgegenstände-Verordnung vom 20.04.2023
  • Hessen§§ 6, 7 JAG Hessen (Fassung der Bekanntmachung vom 15.03.2004, GVBl. I S. 158)
  • Hamburg§ 12 HmbJAG i.V.m. Prüfungsgegenständeverordnung
  • Mecklenburg-VorpommernJAG M-V i.V.m. JAPO M-V vom 16.06.2004 (GVOBl. M-V S. 281); Pflichtfächer nach Inhaltsübersicht in § 11 JAPO M-V (unverified)
  • Niedersachsen§ 3 Abs. 2 NJAG i.V.m. § 16 NJAVO (Prüfungsstoff der Pflichtfachprüfung)
  • Nordrhein-Westfalen§ 11 JAG NRW (Juristenausbildungsgesetz vom 11.03.2003, GV. NRW. S. 135)
  • Rheinland-Pfalz§ 1 Abs. 2 JAPO RP vom 06.07.2023 mit Anlage zu § 1 Abs. 2 Nr. 1 (bis Prüfung Februar 2025: Anlage der JAPO vom 01.07.2003)
  • Schleswig-Holstein§ 14 JAG SH i.V.m. § 3 JAVO (2014: Kernbereiche in § 3 Abs. 3-6; 2023: Pflichtstoffkatalog als Anlage zu § 3 Abs. 2)
  • Saarland§ 8 JAG (Gesetz Nr. 1228 über die juristische Ausbildung idF der Bekanntmachung vom 12.06.2015)
  • Sachsen§ 14 Abs. 3 bis 6 SächsJAPO vom 13.09.2021 (bis 08.10.2021: § 14 SächsJAPO idF der Bek. vom 07.04.2006)
  • Sachsen-Anhalt§ 14 JAPrVO (Ausbildungs- und Prüfungsverordnung für Juristen vom 02.10.2003) i.V.m. JAG LSA
  • Thüringen§ 14 ThürJAPO (Prüfungsstoff) i.V.m. ThürJAG

Switzerland

Exams

  • Aargau: Aargau bar examination
  • Bern: Bern bar examination
  • Basel-Landschaft: Basel-Landschaft bar examination
  • Basel-Stadt: Basel-Stadt bar examination
  • Genève: Geneva bar examination (final examination)
  • Luzern: Lucerne bar examination
  • St. Gallen: St. Gallen bar examination
  • Vaud: Vaud bar examination
  • Zürich: Zurich bar examination

Curricula

  • Universität Basel
  • Universität Bern
  • Universität Luzern
  • Universität St. Gallen (HSG)
  • Universität Zürich
  • Université de Fribourg / Universität Freiburg
  • Université de Lausanne (UNIL)

United Kingdom

Exams

  • SQE1 Functioning Legal Knowledge assessments (FLK1, FLK2)
  • SQE2 practical legal skills assessment (oral and written)

Curricula

  • London School of Economics and Political Science
  • Solicitors Regulation Authority (SRA) / Bar Standards Board (BSB)
  • University of Cambridge
  • University of Oxford

USA

Exams

  • California Bar Examination
  • Multistate Bar Examination
  • Multistate Essay Examination
  • Multistate Professional Responsibility Examination
  • Multistate Performance Test
  • NextGen Uniform Bar Examination
  • Uniform Bar Examination

Curricula

  • American Bar Association, Section of Legal Education and Admissions to the Bar
  • Columbia University
  • Harvard Law School
  • New York University
  • Stanford University
  • University of Chicago
  • Yale University