Privacy Policy

21Stacker Privacy Policy

Last updated: 3rd December 2025

This Privacy Policy explains how 21Stacker (“21Stacker”, “we”, “our”, “us”) collects, uses, stores, and protects your personal information when you enter our global skill-based competitions, use our website, participate in the Affiliate Programme, or submit a free postal AMOE (Alternate Method of Entry).

We act as the data controller for all personal information we process.

You may contact us at:
📧 support@21stacker.com

1. Who We Are

21Stacker operates global skill-based prize competitions where entrants may win prizes denominated in Bitcoin.
We also operate an affiliate referral programme.

We are the data controller responsible for your information.

2. Personal Data We Collect

We collect and process the following categories of data to administer competitions, ensure fairness, prevent fraud, and deliver prizes.

A. Account & Entry Information

  • Full legal name

  • Email address

  • Country/region of residence

  • Login credentials

  • Entry history and participation records

  • Responses to skill questions

  • Entry timestamps and metadata

  • Eligibility confirmations

  • IP address and device data

  • Account activity logs and fraud-prevention signals

B. Winner Verification Data (Winners Only)

If you are selected as a provisional winner, we may request:

  • Government-issued photo ID

  • Proof of address (dated within 90 days)

  • Confirmation of age (18+)

  • Residency verification

  • Additional eligibility evidence

  • U.S. winners only: IRS Form W-9 tax identification data

C. Bitcoin Prize Delivery Information

  • Bitcoin on-chain address (for large prizes)

  • Lightning invoice or request (for smaller prizes)

  • TXID or Lightning payment hash

  • Blockchain metadata required to deliver your prize

We never ask for or store private keys or seed phrases.

D. AMOE (Postal Free Entry) Data

If you enter by post (AMOE), we process:

  • Handwritten AMOE postcard data

  • Full name, email, country of residence

  • Correct skill-question answer

  • Declared Draw Series name

  • Postmark date/time

  • Eligibility details

  • Account-matching information

AMOE postcards are logged internally and securely destroyed after the required retention period.

E. Technical & Anti-Fraud Data

Collected automatically to protect competition integrity:

  • IP address and geolocation approximation

  • Device fingerprints and browser metadata

  • VPN/proxy/TOR detection

  • Session identifiers

  • Duplicate account detection

  • Behavioural pattern analysis

  • Entry validation logs

F. Affiliate Tracking Data (If You Choose to Participate)

  • Referral IDs

  • Click IDs

  • Cookie identifiers (with consent)

  • Attribution metadata

  • Commission assignment records

G. Marketing & Communication Data

  • Email preferences

  • Interaction and click history

  • Competition notifications

  • Consent records

3. How We Use Your Personal Data

We use your data for the following purposes:

A. Operating Competitions

  • Validate eligibility

  • Apply skill-question requirements

  • Process paid entries

  • Match AMOE submissions to accounts

  • Apply entry limits

  • Prevent duplicate or fraudulent entries

  • Conduct provably fair winner selection

  • Deliver Bitcoin prizes

B. Winner Verification & Prize Fulfilment

  • Confirm identity, age, residency, and eligibility

  • Meet anti-fraud and fairness requirements

  • Deliver Bitcoin prizes securely

C. Fraud Prevention & System Integrity

We use personal data to:

  • Detect multiple accounts

  • Identify VPN/proxy usage

  • Enforce region restrictions

  • Prevent manipulation of draws

  • Monitor suspicious activity

  • Block prohibited entrants

  • Ensure fair AMOE handling

D. Legal & Regulatory Compliance

Including:

  • Consumer protection obligations

  • Gambling-/lottery-law exclusions through skill verification

  • U.S. tax reporting (W-9, 1099-MISC) where required

  • Record-keeping and audit duties

E. Affiliate Attribution

  • Track referrals

  • Assign lifetime commission

  • Detect fraudulent or invalid referrals

F. Marketing (Only With Consent)

  • Competition updates

  • New draw announcements

  • Promotional offers

You may unsubscribe at any time.

G. Website Operations & Improvement

  • Analyse site performance

  • Identify and fix technical issues

  • Optimise user experience

4. Lawful Basis for Processing (UK GDPR / EU GDPR)

We rely on the following legal bases:

Contractual Necessity

To:

  • Operate competitions

  • Process entries

  • Provide account services

  • Deliver prizes

Legitimate Interests

To:

  • Prevent fraud

  • Ensure fair competition

  • Protect platform security

  • Run AMOE and skill-verification processes

  • Track referrals for affiliate attribution

  • Maintain system integrity

Legal Obligation

To:

  • Maintain tax and accounting records

  • Provide IRS tax reporting for U.S. winners (W-9 / 1099-MISC)

  • Comply with consumer protection requirements

Consent

Used for:

  • Marketing emails

  • Non-essential cookies

  • Affiliate tracking cookies

Consent may be withdrawn at any time.

5. How We Share Personal Data

We do not sell your data.

We may share limited data with:

A. Service Providers

  • Hosting and cloud services

  • Email automation

  • Verification tools

  • Fraud-prevention services

  • Affiliate tracking systems

  • Postal mail handling (AMOE logging)

B. Legal & Regulatory Authorities

Only where required:

  • ICO

  • IRS (U.S. winners)

  • Law enforcement

  • Courts

  • Regulatory investigations

C. Public Winner Announcements

We may publish for transparency:

  • First name

  • Last name initial

  • Region/country

  • Prize tier

You may request anonymisation where legally permissible.

6. International Data Transfers

Where data is transferred outside the UK/EEA (e.g., to U.S. service providers), safeguards may include:

  • UK International Data Transfer Addendum

  • EU Standard Contractual Clauses (SCCs)

  • Adequacy decisions

  • GDPR-compliant processor agreements

7. Data Retention

We retain personal data only as long as needed.

  • Account data: retained until deletion request

  • Competition entry data: up to 12 months after draw

  • Winner verification: 12 months after prize fulfilment

  • AMOE postcards: securely destroyed within 6 months

  • U.S. tax forms (W-9 / 1099-MISC): retained per IRS rules (3–7 years)

  • Affiliate records: retained for active affiliates, deleted on termination

  • Marketing: until you unsubscribe

After expiry, data is deleted or anonymised.

8. Your Data Protection Rights (UK & EU GDPR)

You have the right to:

  • Access your data

  • Correct inaccurate data

  • Request deletion (“right to be forgotten”)

  • Restrict processing

  • Object to processing

  • Request data portability

  • Withdraw consent

  • Lodge a complaint with the ICO (UK)

Requests may require identity verification.

Email: support@21stacker.com

9. Cookies & Tracking Technologies

We use cookies to:

  • Ensure core site functionality

  • Track affiliate referrals

  • Analyse performance

  • Improve usability

  • Deliver marketing (with consent)

Non-essential cookies (analytics, affiliate, marketing) require explicit consent.

See our Cookie Policy for full details.

10. Security

We use technical and organisational measures including:

  • SSL encryption

  • Firewalls

  • Access controls

  • Encrypted storage of winner documents

  • Fraud-monitoring tools

  • Secure deletion processes

No online system is entirely risk-free, but we take appropriate steps to protect your information.

11. Region Restrictions & Compliance

We may block access to:

  • Prohibited jurisdictions

  • Sanctioned countries

  • Regions where competitions are restricted by law

Your location may affect eligibility.

12. Complaints

If you believe we have mishandled your data, please contact:

📧 support@21stacker.com

You may also lodge a complaint with the ICO:
https://www.ico.org.uk

13. Changes to This Policy

We may update this Privacy Policy as needed to reflect:

  • legal changes

  • security improvements

  • operational updates

Material changes will be posted on this page with a revised date.

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