Global Equity Momentum (GEM) Strategy

Overview

Global Equity Momentum ("we", "our", or "us") is committed to protecting your privacy. This privacy policy explains how we handle data when you use our website, portfolio dashboard, and Google Sheets extension.

We offer two distinct services with different data collection practices:

Google Sheets Extension: Minimal data collection - only ticker symbols and calculation parameters
Web Dashboard: Requires account creation to save your ETF portfolios and enable email notifications

We are committed to privacy-first design and only collect data necessary to provide our services. We never sell or share your data with third parties for marketing purposes.

Information We Collect and Process

Google Sheets Extension (Public API)

When you use our Google Sheets extension, we process:

ETF Ticker Symbols: Symbols you provide in formulas (e.g., "SPY", "VEU") for momentum calculations
Date Ranges: Time periods for calculations (months, days, or custom date ranges)
API Key: Your authentication token for API access (stored in your Google account, hashed on our servers using SHA-256)
Usage Metadata: API endpoint accessed, timestamp, and success/failure status for rate limiting (1000 requests/day default limit)

We do NOT access: Your spreadsheet content, formulas, other cell data, or any personally identifiable information.

Web Dashboard (Authenticated Service)

When you create an account on our web dashboard, we collect and store:

Account Information: Email address and optional display name (managed by Firebase Authentication)
ETF Portfolios: Custom ETF sets you create, including portfolio names and ticker symbols
Notification Preferences: Email notification settings (enabled/disabled, monthly rebalance day 1-31)
Portfolio State: Current top performer and last calculation date for change detection
Notification History: Record of emails sent to prevent duplicates (checked within 23 hours)
API Tokens: Generated tokens for Google Sheets extension (hashed, with name, creation date, usage count, and daily limit)

How We Use Your Data

Momentum Calculations: Process ticker symbols and date ranges to compute 12-month momentum values
Portfolio Management: Store and track your custom ETF sets for easy access across sessions
Email Notifications: Send monthly rebalancing alerts and immediate notifications when your top performer changes (only if enabled)
API Authentication: Validate API tokens and enforce rate limits to prevent abuse
Service Optimization: Cache public ETF price data to improve performance and reduce costs

Google Sheets Extension Permissions

Our Google Sheets extension requires the following OAuth scopes:

spreadsheets.currentonly

Purpose: Add custom functions (MOMENTUM_MONTHS, MOMENTUM_DAYS, MOMENTUM_RANGE) to your active spreadsheet

What we access: Only the ability to write calculation results to cells where you use our functions

What we DON'T access: We do not read, store, or transmit any of your spreadsheet data, formulas, or content

script.external_request

Purpose: Fetch real-time ETF price data and momentum calculations from our secure API

Data transmitted: Only ticker symbols (e.g., "SPY"), date ranges, and your API key for authentication

API endpoint: https://global-equity-momentum.com/api/v1/momentum

Security: All requests are encrypted using HTTPS

Data Storage and Third-Party Services

We use the following third-party services to operate our platform:

Firebase (Google Cloud Platform)

Purpose: User authentication, database storage, and application hosting

Data stored:

User accounts (email, display name, user ID)
ETF portfolios and notification preferences
Cached ETF price data (public market data, updated daily)
API token hashes and usage logs

Data location: United States (Google Cloud servers)

Brevo (formerly Sendinblue)

Purpose: Send email notifications for portfolio rebalancing alerts

Data transmitted: Your email address, display name, ETF set name, and top performer information (only when notifications enabled)

Sender address: noreply@global-equity-momentum.com

Vercel

Purpose: Website hosting and edge computing

Data processed: HTTP requests, API calls (no personal data logged)

Local Storage (Google Sheets Extension)

Your API key is stored securely in your Google account's user properties (PropertiesService.getUserProperties()). This data never leaves Google's systems except when making API requests.

Calculation results are cached for 1 hour in Google's cache service to improve performance.

Email Notifications

If you enable email notifications in the web dashboard, we will send:

Monthly Updates: Sent on your chosen rebalance day (1-31 of each month) with current top performer and 12-month momentum values
Immediate Change Alerts: Sent when top performer changes mid-month (optional)

Frequency control: We prevent duplicate notifications by checking if a similar email was sent within the last 23 hours.

You can disable notifications at any time from your dashboard settings.

Data Security

We implement industry-standard security measures:

HTTPS Encryption: All API requests and website traffic encrypted in transit using TLS
Token Hashing: API tokens are hashed using SHA-256 before storage; plain text tokens are only shown once at creation
Firebase Authentication: Industry-standard user authentication with secure session management
Rate Limiting: Daily API request limits (1000/day default) prevent abuse
Database Security: Firestore security rules prevent unauthorized access; all authenticated operations use server-side Firebase Admin SDK
Minimal Logging: We log errors and API usage statistics, but do not log personal data or calculation details

Cookies and Tracking

We do not use cookies, analytics, advertising trackers, or any third-party tracking technologies.

Firebase Authentication may use session cookies to maintain your login state. These cookies are essential for the service to function and are not used for tracking or advertising purposes.

Data Retention and Deletion

ETF Price Cache: Retained permanently for performance (public market data only)
User Accounts: Retained until you delete your account
Notification History: Retained for duplicate prevention (23-hour check window)
API Usage Logs: Retained for rate limiting and abuse prevention

To delete your data, you can revoke your API tokens and delete your account from the dashboard settings. To request complete data deletion, contact us at support@gem-calculator.com.

Your Rights

You have the right to:

Access: Request a copy of your stored data
Modify: Update your ETF portfolios and notification preferences
Delete: Revoke API tokens and delete your account
Opt-Out: Disable email notifications or stop using the service at any time
Revoke Permissions: Remove Google Sheets extension access through your Google Account settings

GDPR and CCPA Compliance

European Users (GDPR):

For dashboard users, we process personal data (email address) with your consent when you create an account. You have the right to access, rectify, erase, restrict processing, data portability, and object to processing. Contact us to exercise these rights.

Google Sheets extension users: We do not process personal data as defined by GDPR. Ticker symbols and calculations are not considered personal information.

California Users (CCPA):

We do not sell or share your personal information. Dashboard users have the right to know what data we collect, request deletion, and opt-out of data processing. Contact us to exercise these rights.

Children's Privacy

Our service is not directed to children under 13 years of age. We do not knowingly collect information from children. If you believe a child has provided us with personal information, please contact us immediately.

Changes to This Privacy Policy

We may update this privacy policy from time to time. Changes will be posted on this page with an updated "Last Updated" date. For material changes, we will notify dashboard users via email. Continued use of our service after changes constitutes acceptance of the updated policy.

Contact Us

If you have questions about this privacy policy or our data practices, please contact us:

Email: support@global-equity-momentum.com

Website: global-equity-momentum.com

Privacy-First Design

Our service is built with privacy as a core principle. We only collect data necessary to provide momentum calculations and portfolio management features. We never sell or share your data with third parties for marketing purposes.