Ask EY Tax · Korean tax law

Tax research grounded in law,
delivered as documents

Global Tax Analyzer is EY's tax AI platform tuned to Korean tax law. One question retrieves statutes, authoritative interpretations, tribunal decisions and court cases in real time, answers with the evidence, and turns it into ready-to-use documents — opinion letters and memos.

Built by practicing EY tax professionals Evidence-grounded answers Citation status made explicit Specialized agents per task 한국어 · English
Executive Summary · At a glance
Governing Message

Tax answers you cannot trace are answers you cannot use. Global Tax Analyzer checks statutory and case citations against official texts, and clearly flags any that remain unresolved — then connects the evidence to ready-to-use documents and EY professional review.

01

Live retrieval, not memory

Every question retrieves statutes, authoritative interpretations, tribunal decisions and court cases directly from official data — new amendments and cases apply immediately, with no retraining.

02

Every citation verified before display

Existence, the article's paragraph and subparagraph, decision dates and quoted excerpts are all checked against the original text. Unconfirmed citations are filtered out, and anything outside automatic lookup is honestly marked as such.

03

Completed with documents and experts

Download opinion letters, memos and response statements in firm templates — and matters that call for judgment are handed on to your EY tax professional.

Why Global Tax Analyzer

Not an AI that asserts answers — one that shows the evidence and the risk.

This isn't a general chatbot with tax bolted on. Global Tax Analyzer was designed and built by practicing EY tax professionals — it finds the actual statutes and cases, and checks every citation against the official source.

EY BUILT

An AI made by people who know tax

Tax practice and verification principles are implemented in code. Core determinations — rates, valuation, risk — are computed by deterministic engines; the AI writes the explanation and the document on top. Plausible-but-wrong answers have nowhere to hide.

Exhibit 1 Public AI vs GTA — a verification view

General AI

  • Answers from training memory — unaware of recent amendments and cases
  • Invents non-existent provisions and precedents
  • States a conclusion even when it confuses the paragraph or subparagraph
  • Presents summaries and paraphrases as if quoting the source
  • No way to verify the source
  • Data may flow to external models
  • Global Tax Analyzer

  • Live lookup of official data on every question
  • Every citation checked against the source — unconfirmed ones removed or clearly flagged
  • Cross-checks down to the paragraph & subparagraph — fixes the wrong one, keeps no unconfirmed one
  • A quote that differs from the source is replaced with the actual wording — or labeled a gist
  • Evidence cards with a link to the source on each answer
  • Processed within your boundary · never used for training
  • Evidence, not recollection

    Every question triggers a live lookup of official data. Newly amended statutes and fresh case law are reflected instantly — no retraining.

    Statutory and case citations are checked against official sources; unresolved ones are flagged

    We cross-check every statute and case citation against the official source for two things: whether it actually exists and whether the quoted wording matches the original. We check down to the paragraph and subparagraph — a wrong one is corrected to the right one, and a reference we cannot confirm is never left in the answer; the checking is never handed back to you as homework. A quoted excerpt that differs from the source is fixed to the actual wording or labeled as a gist, so an unverified sentence never looks like a verbatim quote. Decision and judgment dates are also checked against the official source. Citations that remain unconfirmed are flagged with their verification status. Answers never use an internal search tool or storage path as a proxy for reliability; status is described only through the original text, identifier, applicable date, and available text scope. The soundness of interpretation and application, however, is flagged as an expert-review matter — existence checking is never dressed up as a guarantee of correctness.

    Judged under the law of the time

    Enter a tax year or transaction date and the analysis runs under the law in force then — exactly what claims for correction, audit defense and prior-year reviews require.

    Choose and control the data boundary

    Organization-scoped access, retention, and no-training rules apply. When a selected external model is used for inference, only the required input is sent under the contractual security configuration; customer-owned cloud and on-premises isolation are also available.

    What you can do
    01PRODUCT WORKFLOW

    Ask, review, receive as a document

    Tax research chat

    Ask an issue and it synthesizes statutes, rulings, interpretations, tribunal and court decisions — with a confidence level, and a review-required flag for high-risk matters.

    Ready-to-use deliverables

    Turn research into opinion letters, memos, emails and briefs — export to PDF · Word · Hangul (HWP), or into your own corporate template.

    See the evidence — even non-experts

    A table shows which sentence of which source each judgment rests on. Every basis leads with its type ( statute · interpretation · precedent) and a plain-language read, so you can follow the reasoning without any tax expertise. Tap a number to open the source.

    Review on your own files

    Attach contracts or internal memos in PDF, Word, HWP, HWPX or text and the review reflects your facts. The original file is not retained; extracted text and its search index are used only for that review, automatically deleted within one week, and never used for model training.

    Connect to EY experts

    When a matter needs human judgment beyond AI review, it hands off smoothly to the responsible EY tax professional.

    Korean · English

    Interface and deliverables in both Korean and English — ready for global reporting and cross-border work.

    Specialized agents
    02SPECIALIST AGENTS

    Task-specific agents — carrying research into recurring work

    Beyond the general research chat, dedicated agents are built for recurring tax workflows. Agent availability and feature scope are provided selectively by contract and plan, and some agents are for EY internal use only — certain features such as diagnostics provide summary-level results, with in-depth review delivered through EY professional engagements.

    Contract Tax AnalyzerTax issues, withholding and risk in contracts
    Tax Risk AnalyzerAssess tax exposure of deals and structures
    Second OpinionIndependent tax opinion on an existing position
    Legislative AnalysisAmendment history, intent and review of a provision
    Tax Amendment AnalysisPending bills vs. current law — changes, intent and impact (with expert review reports)
    Rulings & Precedent AnalysisTax Incentives trends across investment, strategic technology, R&D and employment
    Claim for Correction ReviewSpots refund opportunities in shifting rulings and precedents and builds the logic for a claim for correction
    Bid Notice MonitoringCollects Korea ON-line E-Procurement (나라장터) tax advisory RFPs with deadline tracking and relevance screening
    DART Company AnalysisFind tax-credit advisory candidates, such as semiconductor companies with 20%+ operating margins
    Customs & Trade ResearchHS classification, tariff rates (incl. FTA) and import/export requirements from official databases, with Korea Customs Service rulings and tribunal decisions
    Tax Due Diligence · DiagnosticsSupport for DD and diagnostic work
    Tax Audit DefenseAnalyze notices, build response arguments
    TARAS / UTPReview of uncertain tax positions
    Unlisted Stock ValuationDeterministic valuation & workpapers under the law
    Acquisition Tax ReviewSupport acquisition-tax determinations
    R&D Tax Credit AutomationOrganize R&D tax-credit materials
    Tax R&DCompare new rulings and cases against existing interpretations and pending bills (EY internal)
    EY THORDaily radar over policy, legislation, industry and rulings — tagged by statutory strategic-technology field and tax topic (EY internal)
    Why you can trust it
    03TRUST BY DESIGN

    Accuracy and security by design

    Exhibit 2 Platform at a glance
    6,500+
    National & local tax articles, always available
    10+
    Real-time evidence sources
    Source-checked
    Citations identified in the answer re-verified against official text
    KO·EN
    Bilingual support

    Evidence that never goes dark

    The full body of national and local tax legislation is kept available, so statutory lookups don't stop even during an external outage.

    Honest about limits

    Citations that can't be auto-verified are never silently deleted — they're flagged "verify directly." We never conclude something "doesn't exist" just because our search didn't find it — no official database has complete case-law or ruling coverage, so rather than deleting a real citation and breaking trust, we mark it "outside automatic lookup" and point you to the source. A confidence level is stated too.

    Enterprise security

    Access control, concurrent-session management and audit logging are built in; models range from the in-house engine to frontier LLMs by contract. Models, usage limits, incident alerts and privacy controls are changed through a role-gated admin control plane with an audit trail.

    The order in which evidence is found is part of accuracy. When a case or ruling number and date are supplied, the platform resolves that exact source first; spaces, hyphens, and Unicode dashes are normalized as the same identifier. It then expands from the source's legal issue, while low-relevance evidence is never kept merely to fill a quota. It also checks the latest Supreme Court precedent that actually cites the key Article and scans for later change or overruling signals. Conclusions follow the law applicable at the transaction date → authority hierarchy → recency among evidence of the same authority and issue; changes from earlier positions are disclosed, not hidden.

    Exhibit 3 Live evidence sources
    Statutes · Enforcement Decrees · Rules Annexes · schedules · rate tables NTS rulings Legal interpretations Tax Tribunal Supreme Court Lower courts Constitutional Court · Tax treaties NTS examination requests DART filings Bills · review reports Local ordinances Published guides EY publications (Tax Alert, weekly)

    Just ask. From "repudiation of wrongful calculation on a low-price transfer to a related party" to contract review and unlisted-stock valuation — one line of question comes back as evidence and a document.

    Judgment principles
    04TEMPORAL VALIDATION

    Even with a fresh Supreme Court decision, we first ask: "which law actually applies to this year?"

    Tax law changes often, and a court decision interprets the law as it stood at the time. So before ranking authorities, the platform first confirms which statute version applies to your taxable year and whether it has since been amended.

    Live official lookup + an in-house tax corpus

    Statutes, cases and rulings are fetched live from official sources, and the latest or hard-to-find materials are supplemented from our own accumulated corpus. Citations from both paths are checked against the original text before they appear.

    Temporal applicability & amendment checks

    We verify which statute version a precedent or ruling interpreted; if the law has since changed, it is not used as direct authority for today's conclusion. Older materials are kept — clearly marked as prior doctrine and amendment background — rather than deleted.

    When courts and the tax administration differ, we say so

    Court reasoning and current administrative practice can diverge. We present both sides rather than one, and explain the practical burden this can create at filing or appeal.

    When certainty isn't possible, we show the way to get it

    Sources that cannot be verified carry their verification status and limits, stated as such. Where useful, we point to official advance-ruling procedures (NTS advance answers, written inquiries) or expert review — reducing uncertainty before you act.

    How it's used
    05PLANS & ROLLOUT

    Adopt as much as you need — governed at the organization level

    Usage is managed transparently in credits. The in-house tax engine runs without limits; premium models are chosen only when you need more power. Scale and rates are configured to fit each contract.

    Core research is included

    Research and review on EY's dedicated GTA engine come with a generous allowance included in your plan. The scope of inclusion is configured per contract.

    Premium models when you need them

    For matters that call for deeper reasoning, you can select a frontier model. Only premium usage is metered in credits — you pay for what you use.

    Managed at the organization level

    Administrators assign seats, credit limits, and model access per organization and member, with usage visible transparently on a dashboard.

    Configured per contract

    Scope, model mix, and rates are designed around the size and needs of your division or entity. Enterprise agreements and dedicated-model integration are supported.

    Transparent cost, complete output

    Cost is governed through concurrency, queueing, and limits — we never shorten output to save cost. Even long review memos are completed end to end.

    Data stays within the contract boundary

    Uploaded materials and conversations are separated by organization-scoped access and retention policy and are not used to train models. Contract terms govern external-model processing; dedicated-cloud or on-premises isolated deployment is available.