Legal

Privacy Policy

Last updated: February 23, 2026

This Privacy Policy describes how Kerna sp. z o.o. ("Kerna", "we", "us", or "our") collects, uses, stores, and discloses information when you use the Kerna Google Workspace add-on, website (kerna.io), and related services (collectively, the "Services"). By accessing or using our Services, you agree to the practices described in this Policy.

1. Data Controller

The data controller responsible for your personal data is Kerna sp. z o.o., a company registered under the laws of the Republic of Poland, with its principal place of business in Katowice, Poland.

For all data protection inquiries, you may contact us at: privacy@kerna.io

2. Information We Collect

We collect only the minimum information necessary to authenticate your identity, deliver our Services, and manage your subscription.

2.1 Account and Authentication DataAll user authentication is handled via Google OAuth (Google Sign-In). We do not create, manage, or store passwords. Upon authentication, we receive and store your email address and display name as provided by Google. This data is used to identify your account, manage sessions, and associate your subscription.

2.2 Subscription and Billing DataAll financial transactions are processed by Stripe, Inc. Kerna does not collect, transmit, or store credit card numbers, billing addresses, or security codes (CVC/CVV). We retain only a tokenized reference to your Stripe customer ID, subscription status (e.g., active, cancelled), plan tier, and billing cycle dates. This data is stored in Google Cloud Firestore.

2.3 Usage MetricsWe track token consumption (the number of AI processing units used) per user and per team to enforce plan limits and display usage dashboards. We also collect anonymous, aggregated telemetry data such as feature usage frequency, error rates, and response times. This data is strictly technical and is never linked to specific email content.

2.4 User PreferencesWe store your chosen language, tone preference, and display settings in Firestore so that the add-on can operate consistently across sessions.

2.5 Early Access and Contact SubmissionsIf you submit your email address via an early access form or contact form on our website, we store that email address and submission timestamp for the sole purpose of contacting you about product availability or responding to your inquiry.

3. Information We Do Not Collect

The following categories of data are never collected, stored, logged, cached, or written to any persistent storage system by Kerna:

Email message bodies, subjects, or headers
Sender or recipient email addresses from processed emails
Attachment content or metadata
AI-generated summaries, replies, translations, or drafts
Calendar event content, contact details, or spreadsheet data accessed during user-initiated actions
Google account passwords or OAuth refresh tokens beyond what is required for active session management

4. Zero Retention Architecture

Kerna adheres to a strict "Zero Retention" policy regarding all user communication content. This is a core architectural principle, not a configurable setting.

4.1 Ephemeral ProcessingWhen you explicitly trigger an AI action (e.g., Summarize, Reply, Translate, Compose, Extract, or Rewrite), the text content of the relevant email thread is transmitted to our AI inference provider via an encrypted connection. The content is held in volatile memory only for the duration required to process your request and generate a response. Once the response is delivered to your Gmail sidebar, the source content is immediately discarded. No email content is written to any database, log file, or persistent storage system.

4.2 No Background ProcessingKerna operates exclusively on user-initiated actions. The add-on does not passively scan, index, monitor, or archive your inbox, calendar, contacts, or any other Google Workspace data in the background. Every interaction with your data requires your explicit input.

4.3 No Model TrainingYour data is never used to train, fine-tune, retrain, or improve any artificial intelligence or machine learning model — whether operated by Kerna, OpenAI, Google, or any other party. Your inputs remain private to your specific request session.

5. How We Use Your Information

We use the information described in Section 2 for the following purposes:

To authenticate your identity and maintain your session
To provide, operate, and improve the Services
To manage your subscription, process billing events, and enforce plan limits
To display your usage statistics and preferences within the add-on and dashboard
To send transactional communications (e.g., subscription confirmations, billing receipts)
To respond to your support or contact inquiries
To detect, prevent, and address technical issues, abuse, or security incidents
To comply with applicable legal obligations

We do not sell, rent, or lease your personal information to any third party. We do not use your data for advertising, profiling, or automated decision-making.

6. Third-Party Sub-Processors

We use the following third-party services to operate Kerna. Each sub-processor receives only the minimum data necessary to perform its function.

Provider	Purpose	Data Shared
OpenAI	AI inference (GPT-4, GPT-5)	Anonymized text prompts only. No personal identifiers, no email addresses, no account data.
Stripe	Payment processing	Email address for customer identification. All payment details are handled directly by Stripe.
Google Firebase	Authentication, database, hosting	Account data, subscription status, usage metrics, and preferences as described in Section 2.
Google Analytics	Website analytics	Anonymous, aggregated website usage data. Subject to consent (see Section 9).

We maintain Data Processing Agreements (DPAs) with all sub-processors that handle personal data. Our agreements with OpenAI and Google explicitly prohibit the use of transmitted data for model training or improvement.

7. Google API Services Compliance

Kerna's use and transfer of information received from Google APIs to any other app will adhere to Google API Services User Data Policy, including the Limited Use requirements.

In accordance with the Limited Use requirements, we affirm the following:

Limited Purpose: We only use data obtained through Google APIs to provide and improve the user-facing features that are prominent in the application's interface — specifically, AI-powered email reply, summarization, translation, composition, extraction, and rewriting. We do not use Google API data for any other purpose.
Prohibited Transfer: We do not sell, rent, or transfer Google API data to third parties. We do not use Google API data for serving advertisements. Data is only transmitted to our AI inference provider (OpenAI) to fulfill the specific, user-initiated feature request, and only the minimum text context necessary is sent.
Prohibited Personnel Access: We do not allow humans to read user data obtained through Google APIs, except (a) with the user's affirmative agreement for specific messages (e.g., for technical support at the user's request), (b) where necessary for security purposes such as investigating abuse, or (c) to comply with applicable law.
Data Minimization: We only request the minimum necessary OAuth scopes required to perform the specific features of the application. We do not request broader access than what is needed for the translation, summarization, reply, composition, extraction, and rewriting features described in Section 8.

8. Google Workspace Permissions

Kerna requests the following Google Workspace permissions. Each permission is used exclusively for user-initiated actions and is never exercised in the background.

Gmail — Read—Read the content of the current email thread when you trigger Summarize, Reply, Translate, Extract, or Rewrite.

Gmail — Compose—Insert AI-generated drafts into your compose window when you trigger Reply or Compose.

Google Calendar — Read—Check for scheduling conflicts when you extract event details from an email.

Google Calendar — Write—Create calendar events from extracted dates and times, only when you explicitly confirm.

Google Contacts — Read/Write—Look up or add contacts when you explicitly request contact-related actions.

Google Sheets — Read—Access spreadsheet data (e.g., email lists) only when you explicitly direct Kerna to do so.

No data accessed through these permissions is stored, logged, or transmitted beyond the immediate, ephemeral processing described in Section 4. Kerna only requests the minimum necessary scopes to perform its features. Kerna cannot and does not perform any action without your explicit initiation.

9. Cookies and Analytics

9.1 Website (kerna.io)Our website uses Google Analytics (GA4) to collect anonymous, aggregated usage data such as page views, session duration, and traffic sources. Google Analytics cookies are loaded only after you provide consent via our cookie consent banner, in compliance with the EU ePrivacy Directive and GDPR. You may withdraw consent at any time by clearing your browser cookies or adjusting your cookie preferences.

9.2 Google Workspace Add-onThe Kerna add-on running inside Gmail does not use cookies. It operates within the Google Apps Script environment and relies on Google's built-in session management. No third-party tracking scripts are loaded within the add-on.

9.3 Essential CookiesOur website uses strictly necessary cookies for authentication (Firebase Auth session) and security. These cookies do not require consent under GDPR, as they are essential to the operation of the service.

10. Data Security

We implement industry-standard technical and organizational measures to protect your data:

All data in transit is encrypted using TLS 1.2 or higher.
All data at rest in Firestore is encrypted using AES-256 encryption managed by Google Cloud.
API keys and secrets are stored using Firebase Secret Manager, never in source code.
Access to production systems is restricted to authorized personnel using role-based access controls.
Firestore security rules enforce document-level access control, ensuring users can only access their own data.
We do not store email content, so the attack surface for sensitive data exposure is architecturally minimized.

While we implement robust security measures, no system is completely secure. In the event of a data breach affecting your personal data, we will notify you and the relevant supervisory authority within 72 hours as required by GDPR Article 33.

11. International Data Transfers

Kerna is based in the European Union (Poland). Your account data is stored in Google Cloud Firestore, which operates within Google's global infrastructure with data residency controls.

Certain sub-processors — including OpenAI and Stripe — may process data in the United States. All such international transfers comply with GDPR Chapter V requirements. We ensure adequate safeguards through Standard Contractual Clauses (SCCs) incorporated into our Data Processing Agreements with each sub-processor.

Email content transmitted for AI processing is ephemeral and is not stored at any point during or after the transfer. This significantly reduces the risk profile of any international data transfer involving communication content.

12. Data Retention

Data Category	Retention Period
Email content (processed)	Zero. Discarded immediately after processing.
Account data (email, name)	Retained while your account is active. Deleted within 30 days of account deletion.
Subscription and billing data	Retained while your subscription is active. Billing records retained for 7 years for tax compliance.
Usage metrics (token counts)	Retained while your account is active. Reset each billing cycle.
Preferences (language, tone)	Retained while your account is active. Deleted with account.
Analytics data (GA4)	Retained for 14 months per Google Analytics default configuration.
Early access / contact submissions	Retained until product launch or inquiry resolution. Deleted upon request.

13. Your Rights Under GDPR

If you are located in the European Economic Area (EEA), you have the following rights under the General Data Protection Regulation:

Right of Access: You may request a copy of the personal data we hold about you.

Right to Rectification: You may request correction of inaccurate or incomplete personal data.

Right to Erasure: You may request deletion of your personal data ("Right to be Forgotten"). Upon request, we will delete your Firestore account data within 30 days.

Right to Restrict Processing: You may request that we restrict the processing of your personal data under certain circumstances.

Right to Data Portability: You may request your personal data in a structured, commonly used, machine-readable format.

Right to Object: You may object to the processing of your personal data for specific purposes.

Right to Withdraw Consent: Where processing is based on consent (e.g., analytics cookies), you may withdraw consent at any time without affecting the lawfulness of prior processing.

To exercise any of these rights, please contact us at privacy@kerna.io. We will respond within 30 days. If you are unsatisfied with our response, you have the right to lodge a complaint with your local data protection supervisory authority. In Poland, this is the President of the Personal Data Protection Office (UODO).

14. Children's Privacy

Our Services are not directed to individuals under the age of 16. We do not knowingly collect personal data from children. If we become aware that we have collected personal data from a child under 16, we will take steps to delete that information promptly. If you believe we have collected data from a child, please contact us at privacy@kerna.io.

15. Changes to This Policy

We may update this Privacy Policy to reflect changes in our practices, technology, or legal requirements. We will notify you of material changes by posting the updated Policy on this page and updating the "Effective Date" above. For significant changes affecting how we process your data, we will provide prominent notice via the add-on or email. We encourage you to review this page periodically. Continued use of the Services after changes constitutes acceptance of the updated Policy.

16. Contact Us

For any questions, concerns, or requests regarding this Privacy Policy or our data practices:

Data Controller: Kerna

Location: Katowice, Poland

Privacy inquiries: privacy@kerna.io

General inquiries: contact@kerna.io

Last updated: February 23, 2026

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