CasusLegalTAXTax law
Specialised CasusLegal connector
The Tax Code in different versions, letters from the Federal Tax Service and Ministry of Finance, and case law. Connect Tax to an AI application and work with the sources in a single dialogue.
For tax lawyers, accountants and finance professionals.
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Instructions with screenshots on CasusLegal →Based on the published indexes dated 22 and 26 October 2026. ¹ Including selected items from reviews and clarifications.
Contents and coverage
The main CasusLegal database contains case law from various areas of law. Tax contains a tax-specific selection supplemented by versions of the Tax Code of the Russian Federation and agencies’ letters.
Both parts of the Tax Code of the Russian Federation. The text of an article or paragraph, amendment history, comparison of versions, and searches for provisions by the meaning of a question.
Clarifications on the application of tax legislation. Search by subject, details, and wording; access the letter text.
The earlier years of Ministry of Finance letters are represented by individual documents; the main body of the collection dates from 2018 onward.
A subject-specific selection of case law from the Constitutional Court of the Russian Federation, Supreme Court of the Russian Federation, Supreme Commercial Court of the Russian Federation, administrative cases of the Supreme Court of the Russian Federation (the KAS database), and the commercial courts of ten districts.
The dates relate to materials included specifically in Tax: the higher-court database covers the period from 19 March 1993; each of the ten commercial cassation court districts covers the period from January 2014. This is a subject-specific selection, not a complete archive of all acts from those periods.
Federal Tax Service letters: 14 January 2021 — 28 September 2026 ; Ministry of Finance letters: 4 October 2010 — 10 September 2026 . The latest judicial acts in the selection are dated 28 September 2026. The Tax Code of the Russian Federation is represented by snapshots based on the export dated 23 October 2026. Later documents should be checked separately.
54 044 case-law entries include 720 individual items. The letters contain 3 280 standalone documents and a further 231 entries for individual items. The number of search entries does not equal the number of court cases.
Provisions for the relevant period
Enter the date of the transaction, open the provision applicable during that period, and compare it with a later version.
The Tax Code is stored as snapshots, primarily as of the beginning of each year and on specific dates within the year. If changes were made between snapshots, the exact date on which they entered into force must be verified against the amending law. Future versions are marked separately.
QUERY EXAMPLE
Open Article 145 of the Tax Code of the Russian Federation for a transaction in 2024. Specify the snapshot date and any changes within the period, if there were any. Find letters and case law on the conditions for VAT exemption.
Use the example in a dialogue with Tax connected.
Open testing
Test Tax on your own tasks. A subscription to the main CasusLegal is not required for testing.
The common period for all participants runs until 23:59 Moscow time on 15 November 2026. We will announce the terms of further access separately.
Tax connects sources to your AI application that supports MCP connectors, such as Claude or ChatGPT. The dialogue and preparation of the response take place in your application. Connector availability depends on its settings and plan.
Ask it to specify the version date and the sources’ details. Errors in dates and numbers have been identified in some entries—verify them against the full text. Open the texts of the provisions, letters, and judicial acts on which the conclusion is based. An agency’s position may differ from a court’s position; apply the conclusion in light of the circumstances and period of your transaction.
Your work-related questions will help improve Tax.
Report an error or suggest an improvement Specify the question, period, name of the AI application, and the document with which the problem arose.