Privacy Policy

Grouped by what you are doing. The only items required to open an account are your name, email address and password (or your social sign-in details). Items marked optional are collected only if you choose to provide them; declining them never affects your sign-up or your use of the service, except that a feature which needs that item (for example checkout, which requires phone verification) is unavailable. Everything else is generated or collected automatically as you use the feature concerned.

We do not collect your date of birth, home address, full card numbers, or any of the sensitive categories in PIPA Article 23 (health, religion, political views and similar). Please keep them out of your essays and recordings; if they appear, we treat them as ordinary submission content. Inside the company, your teacher sees your name, email, submissions, scores, attendance and missed work for the classes they teach. Your advisor sees those plus your phone number, KakaoTalk id, goals, motivation notes, enrollment and payment dates, consent history and progress while advisor support is on. Our operators see every record in this policy through an internal console, and each staff opening of a student's dashboard is recorded.

PIPA Article 15 requires a lawful basis for each use. The GDPR article is shown alongside for readers in the European Economic Area.

Criteria for additional use or disclosure: when deciding whether personal information may be used or disclosed beyond the original purpose without new consent under PIPA Articles 15(3) and 17(4), we consider whether the new purpose is related to the original one, whether you could reasonably expect it given how the data was collected and how it is normally handled, whether it unfairly harms your interests, and whether safeguards such as pseudonymization or encryption are in place. We do not currently rely on these provisions; if we ever do, this policy will say so first.

We do not sell personal information and we do not share it for anyone else's marketing. The companies in the table below receive data for the purpose shown, under contract with us. Each receives the items shown in the table. Meta is different: ad-measurement events are disclosed to it only with your cookie-banner consent, and it keeps them under its own policy, as described under Cookies and device storage. Beyond that, we disclose data only to authorities when the law requires it, to our lawyers and accountants under confidentiality, in a merger or sale after notice to you, or with your explicit consent.

When a company changes or a new one is engaged, we announce it in advance as described under Changes to this policy and update this table when the new processing begins. Toss Payments, Kakao, Google and Naver also act as independent controllers for what happens on their own sites. Some processors subcontract part of their work: Solapi delivers KakaoTalk notifications through Kakao, Vercel AI Gateway forwards evaluation and chat requests to the language model providers in the table, and infrastructure processors such as Vercel, Neon and Upstash run on cloud platforms such as Amazon Web Services. Subcontractors process data only for the same purpose, under the original processor's contract and policy. A few services see only your IP address and browser: the content networks that deliver camera-effect models during live classes (jsDelivr, Google Cloud Storage), the servers that connect live examiner calls (Google and Cloudflare, plus Cloudflare's relay, which passes the call's encrypted audio along without being able to read it when a direct connection fails), and YouTube or Vimeo when a lesson embeds their player. When a class is held on Zoom instead of our own classroom, Zoom receives your display name, camera and microphone under its own policy.

Most of our processors are outside Korea. These transfers are outsourcing and storage needed to perform our contract with you (PIPA Article 28-8(1)(3)). The law asks us to disclose the recipient, the country, the items, when and how, the purpose and retention, contact details, and how to refuse. There is one exception: ad-measurement events go to Meta in the United States as a disclosure to a third party, only with your separate consent on the cookie banner (Article 28-8(1)(1)). Signing in with Google is not a transfer by us: Google sends us your sign-in details, and we send Google nothing about you beyond the sign-in request and, when you delete your account, the request to revoke our access. The table above gives the recipient, items and purpose; the rest follows.

• Website support chat: recipients are Vercel, Inc. (AI Gateway, which relays the request), Anthropic, PBC (answers) and Google LLC (answer check and translation), all in the United States. Items: the text of your messages and answers, and the facts about your own account the assistant looked up (enrollment, next live class, assignments, marks, level test). Purpose: to answer your question, check the answer and let our team read and reply. Retention: the providers keep it only as their terms allow; we keep the thread as described under How long we keep it. Method: in real time over encrypted connections, when you send a message.
• Timing and method: in real time, over encrypted connections, at the moment a feature needs the processing.
• Retention by recipient: each keeps the data only as long as its function needs, under its own policy and our contract. Essays and recordings sent for evaluation are processed at that moment and not used for training under the settings we have chosen.
• Contact details: each recipient's privacy contact is listed in its privacy policy, linked in the table. If you cannot reach them, write to privacy@tieroneenglish.com and we will forward your request.
• Refusing: you may refuse cross-border transfer by emailing privacy@tieroneenglish.com or by deleting your account. Because hosting, storage and evaluation happen abroad, refusal means we cannot provide the service. Refusing the ad-measurement transfer to Meta costs you nothing: decline on the cookie banner.

We keep personal information only as long as the purpose needs, then delete it without delay. The periods below are the ones we apply; most run on scheduled jobs in our system.

• Encryption in transit everywhere (TLS, HSTS), and at rest at our database and storage providers.
• Passwords are stored only as salted hashes. Sessions use HttpOnly, Secure, SameSite cookies and expire after 7 days.
• Rate limits on sign-in, codes, uploads, evaluations and the assistant; signed one-time tokens for email links; webhooks verified by signature or a shared secret.
• Role-based access on every server endpoint. Staff see only what their role needs, and a student's dashboard can be opened by staff only through a logged "view as student" procedure that requires a reason and expires in 30 minutes.
• Student recordings, attachments and profile pictures live in a private storage zone and are served through links that expire, within 6 hours for content you review and 15 minutes for one-off downloads. Teacher and advisor profile pictures are public.
• Every staff opening of a student's dashboard is recorded permanently in our operations database with the operator, the student and the reason. Other security events (sign-ups, sign-ins, payment changes, role changes, deletions) are written to our hosting provider's logs, which are kept for one day.
• Error reports have cookies and credentials stripped before they leave your browser or our servers.
• We limit the staff who handle personal information to the minimum the work requires, and each account carries only the role it needs.
• Our servers and storage sit in the certified data centers of cloud providers, which apply physical controls such as access restriction. We do not keep personal information on paper.

PIPA Articles 35 to 37 give you the right to see, correct, delete and stop processing of your data. Most of it is self-service.

See and download

Settings has a one-click export of your account, profile, consents, enrollments, diagnostic results, exercise history and assistant chat as a file. It leaves out progress snapshots, weekly reports, vocabulary review state, payment keys, ad and campaign identifiers, staff notes, messages with staff, the send log and raw recordings; email us for those.

Correct

Name, phone, picture, goals and preferences are editable in Profile and Settings. Your email address is fixed to your sign-in; email us to change it.

Delete

Settings, confirmed with a one-time code sent to your email. Accounts with a purchase get a 7-day window to cancel, from Settings or the link we email you; others are deleted at once. You cannot start a deletion while a refund is being processed; try again once it is paid out.

Withdraw consent

Marketing messages: toggle in Settings or the unsubscribe link in any marketing email. Advisor support: switch off in Profile. Ad cookies: the Cookie Policy page or the footer link. Confirmations you asked for (waitlist, unfinished order) and progress messages are service messages and are sent regardless of the toggle. Withdrawal does not undo processing already done.

Review sessions

Settings lists every signed-in device with its location and lets you sign any of them out.

Automated decisions

Ask your teacher or support@tieroneenglish.com to explain or review any automatically generated score or feedback, or to have a person redo it (PIPA Article 37-2).

Stop processing or object

Email privacy@tieroneenglish.com. We answer within 10 days and may ask you to confirm your identity from your registered email.

Beyond the self-service options above, you can request access, correction, deletion, suspension of processing or withdrawal of consent by email at privacy@tieroneenglish.com or by phone at 070-8018-6673. We respond within 10 days of receiving a request. If we limit or refuse access, or cannot honor a deletion or suspension request, we tell you why and how to object. Personal information that another law requires us to keep (for example payment records kept for 5 years) cannot be deleted during that period. You can also exercise these rights through a legal representative or an agent you authorize in writing; we will ask for a power of attorney or similar proof of authority and verify that the person asking is you or your authorized agent. If you are the parent or guardian of a child under 14 who has registered, contact us and we will remove the account (see Children and sensitive information below).

Our Personal Information Protection Officer handles all privacy questions, requests and complaints, and the same contact point (privacy@tieroneenglish.com) receives and processes requests for access, correction, deletion and suspension of processing.