Privacy Policy
This Privacy Policy explains how Sanderson Management Services Limited handles your personal data when you use the Signal TRT mobile app (the App) and the website at signaltrt.com. We are the data controller responsible for your information.
We have written this policy to be readable. Where the law requires precise terms, we use them and explain what they mean.
Contents
1. Who we are
The data controller is Sanderson Management Services Limited, a company registered in England and Wales (company number 08899035). Our registered office is at Bryndon House, 5/7 Berry Road, Newquay, Cornwall, TR7 1AD, United Kingdom.
We trade as Signal TRT.
We are registered with the Information Commissioner's Office under registration number ZC140805.
For privacy queries, contact us at privacy@signaltrt.com.
2. Data we collect
Website and waitlist data
When you join the waitlist on signaltrt.com before launch, we collect the information you submit and a little context about how you arrived:
- Your email address
- Your platform preference (Android, iPhone, or both)
- Marketing attribution parameters (utm_source, utm_campaign, and utm_medium) read from the link you followed, where present, so we can see which campaign referred you
We use this only to send you launch and product updates about Signal TRT and to understand which campaigns are working. You can unsubscribe at any time using the link in every email, which removes you from the list. This data is stored by Supabase, and the emails are sent via Resend (see “Who we share it with”).
Account data
- Email address
- Name, where you provide it
- Age range or birth year
- Account preferences and settings
Health data (special category data)
With your explicit permission, we read health metrics from Health Connect on Android or HealthKit on Apple devices, including:
- Sleep stages and sleep duration
- Heart rate variability (HRV)
- Resting heart rate and heart rate
- Steps
- Blood oxygen (SpO2)
- Respiratory rate
You can revoke this permission at any time in your device settings, and you can delete imported metrics from within the App.
Bloodwork
- Images you upload from your camera or photo library
- Marker values extracted from those images by optical character recognition (testosterone, oestradiol, SHBG, lipids, full blood count, and others)
- Manual entries you provide
- Reference ranges and notes and context you choose to record
TRT protocol and logs
- Compounds, doses, and frequencies you record
- Injection dates, sites, and notes
- Symptom logs and scenario responses
- Free-text notes you write
Generated content
- AI-generated reviews, daily summaries, bloodwork reports, and daily insights produced from your data
Subscription and payment data
- Subscription status, tier, renewal dates, and transaction identifiers
- Processed via Google Play Billing or the Apple App Store
We do not see or store your payment card details. All card processing is handled by Google or Apple under their own terms and privacy policies.
Technical data
- Push notification token, used by Expo to deliver reminders and notifications
- A stable per-device identifier (Android SSAID or iOS identifier-for-vendor), used only to manage delivery of push notifications to your device
The App does not use third-party analytics, crash-reporting, or advertising tools, and does not collect usage analytics, crash reports, or an advertising identifier.
3. Health data
Health data, including bloodwork, symptom logs, and metrics imported from Health Connect or HealthKit, is special category personal data under Article 9 of the UK GDPR. We process it only with your explicit consent, given through in-app permission prompts and through your continued use of features that depend on it.
You can withdraw consent at any time by:
- Revoking permissions in your device settings (Health Connect or HealthKit)
- Deleting individual logs, bloodwork entries, or images from within the App
- Closing your account, which deletes your data subject to the retention rules below
Withdrawing consent does not affect the lawfulness of processing carried out before you withdrew it.
4. How we use it
We use your data to:
- Create and operate your account
- Let you log symptoms, scenarios, doses, and bloodwork
- Generate AI-assisted reviews, summaries, daily insights, and bloodwork reports based on your data
- Surface patterns in your logs that may be useful for self-reflection or for sharing with your clinic or doctor
- Send push notifications related to logging, reminders, and trial or subscription status
- Send you launch and product updates by email if you have joined the website waitlist, until you unsubscribe
- Process subscription payments and manage trials and renewals
- Maintain security, prevent fraud, and investigate misuse
- Improve the App, fix bugs, and develop new features
- Meet our legal obligations, including tax and accounting
5. Lawful bases
We rely on the following lawful bases under Articles 6 and 9 of the UK GDPR:
| Purpose | Lawful basis |
|---|---|
| Account creation, login, and core App functionality | Contract performance, Article 6(1)(b) |
| Processing health and bloodwork data | Explicit consent, Article 9(2)(a) |
| Subscription billing | Contract performance, Article 6(1)(b) |
| Push notifications | Consent, Article 6(1)(a) |
| Website waitlist signup and launch/marketing emails | Consent, Article 6(1)(a) |
| Security and fraud prevention | Legitimate interests, Article 6(1)(f) |
| Tax and accounting records | Legal obligation, Article 6(1)(c) |
6. Who we share it with
We use a small number of carefully chosen sub-processors to operate the App. We do not sell your data, and we do not share it with advertisers.
| Sub-processor | Purpose | Region |
|---|---|---|
| Anthropic | AI processing for reviews, daily summaries, bloodwork reports, and daily insights via the Claude API | United States |
| Supabase | Database, authentication, server functions, file storage | European Union (Ireland) |
| Expo | Push notification delivery | United States |
| Resend | Sending waitlist welcome and launch update emails, and internal new-signup notifications | United States |
| Google Play Billing | Subscription payments on Android | Per Google terms |
| Apple App Store | Subscription payments on Apple devices | Per Apple terms |
| Cloudflare | DNS, web hosting for signaltrt.com, email routing | Global edge network |
| Microsoft 365 | Email hosting for our support and contact mailboxes | European Union |
Each sub-processor is bound by a written data processing agreement. They process your data only on our instructions and only for the purposes set out above.
We may also disclose data where we are legally required to do so, for example in response to a valid court order or law enforcement request, or to protect our rights or the safety of others.
7. AI processing
The App uses Anthropic's Claude API to generate written content based on your data, including:
- Reviews of patterns across your symptom logs
- Daily summaries and insights
- Bloodwork reports written from values you record
To produce this content, we send the relevant slice of your data to Anthropic's API. This includes health data, your free-text notes, and, when you upload a blood test result, the bloodwork image or PDF itself, which Anthropic's model reads to extract your marker values.
Under our commercial agreement with Anthropic, your data sent through the API is not used to train Anthropic's models. Anthropic's commercial API terms state that API inputs and outputs are not used to train models by default, and standard inputs and outputs are normally deleted from Anthropic's backend within 30 days, subject to limited exceptions such as legal requirements and usage-policy enforcement.
AI-generated content is informational only. It is not medical advice, a diagnosis, or a treatment recommendation. See our Terms of Service for the full position.
8. AI processing using Anthropic Claude
Signal uses Claude, a third-party AI service from Anthropic, to organise your logged information into written summaries, reviews, daily insights and clinic prep documents, and to extract text and values from uploaded blood test documents.
What we send to Anthropic. When AI-written outputs or blood-document extraction are used, we may send Anthropic: your age; your TRT protocol details and dose logs; symptoms, check-ins and notes you log; blood test results; uploaded lab report files, which may include personal details printed by the lab, such as your name, lab reference, clinic details or test identifiers; and heart rate, heart rate variability, sleep and blood oxygen data from Apple Health or Health Connect, if you choose to connect those services.
How we collect this information. This information comes from details you enter in Signal, dose logs you create, notes and check-ins you write, blood test documents you upload, and Apple Health or Health Connect data you choose to share with Signal.
How we use it. We use this information to provide Signal's logging, summary, report, daily insight, blood-document extraction and clinic prep features. Signal does not use Claude to diagnose, assess whether TRT is working, interpret individual results, or recommend treatment or dose changes.
Restrictions on use. We do not sell your information. We do not use health or fitness data for advertising, marketing or use-based data mining. We do not allow Anthropic or any other third party to use Signal API inputs or outputs for advertising, marketing, resale, use-based data mining or AI model training. We share this information with Anthropic only under our commercial API arrangement, which requires it to be protected to a standard consistent with this Privacy Policy, including the restrictions above.
Anthropic's commercial API terms state that API inputs and outputs are not used to train models by default. Standard API inputs and outputs are normally deleted from Anthropic's backend within 30 days, subject to limited exceptions such as legal requirements and usage-policy enforcement.
Consent and withdrawal. Signal asks for your agreement in the app before sending your information to Anthropic. You can stop future AI processing at any time in Settings > Privacy > AI processing. If you turn this off, Signal will stop sending your information to Anthropic and AI-written reviews, reports, daily insights and clinic prep documents will not be available. Withdrawal does not affect processing that already happened before withdrawal. You can also delete your account in Settings, which removes your Signal account and stops future processing.
9. International transfers
Some of our sub-processors operate outside the United Kingdom and the European Economic Area, notably Anthropic, Expo, and Resend, which are based in the United States.
Where we transfer your personal data outside the UK or EEA, we use:
- Standard Contractual Clauses (SCCs) approved by the European Commission, where applicable
- The UK International Data Transfer Addendum issued by the Information Commissioner's Office
- Supplementary technical measures, including encryption in transit and at rest
You can request a copy of the safeguards we use by emailing privacy@signaltrt.com.
10. How long we keep it
| Data | Retention |
|---|---|
| Account data | While your account is active, plus up to 30 days after deletion request |
| Health data, bloodwork, logs, notes | While your account is active. You can delete entries at any time. On account deletion, removed within 30 days. |
| Generated reviews and reports | Stored alongside the data they reference |
| Subscription and payment records | Six years, for UK tax and accounting purposes |
| Backups | Rolling 30-day backup window. Deleted records are permanently removed when they fall out of the backup window. |
| Support correspondence | Up to two years after the last contact |
11. Your rights
Under UK GDPR, you have the right to:
- Access: ask for a copy of the data we hold about you
- Rectification: ask us to correct data that is inaccurate or incomplete
- Erasure: ask us to delete your data, subject to legal exceptions
- Restriction: ask us to limit how we use your data in certain circumstances
- Portability: receive your data in a structured, machine-readable format, and have it transferred to another provider where technically feasible
- Objection: object to processing based on legitimate interests
- Withdraw consent: at any time, where processing is based on consent
- Automated decisions: the App's AI-generated content is informational and does not make legally significant decisions about you. You retain the right to a human review of any decision we make that has a significant effect on you.
To exercise any of these rights, email privacy@signaltrt.com. We respond within one month. We may need to verify your identity before acting.
Right to complain: if you are unhappy with how we handle your data, you can complain to the Information Commissioner's Office at ico.org.uk or 0303 123 1113. If you live in the European Economic Area, you can also complain to your local data protection authority.
12. Security
We protect your data with measures appropriate to its sensitivity:
- TLS encryption for data in transit
- Encryption at rest in our database and storage layers
- Authentication and access controls on all admin and infrastructure interfaces
- Server functions running in isolated environments with credentialled access only
- Regular review of dependencies and security configuration
No system is perfectly secure. If we discover a personal data breach affecting you, we will notify the Information Commissioner's Office within 72 hours where required, and we will notify you directly if the breach is likely to result in a high risk to your rights and freedoms.
13. Cookies and analytics
The App does not use cookies, and the signaltrt.com website does not use cookies either. We do not use advertising cookies or tracking pixels.
The App and the website do not use third-party analytics, tracking, or crash-reporting tools, and we do not use third-party advertising networks.
Our legal and information pages on signaltrt.com (this Privacy Policy, our Terms of Service, and the unsubscribe page) load web fonts from Google Fonts. When one of these pages loads, your browser requests the fonts directly from Google’s servers, so your IP address and basic browser information are shared with Google to deliver them. We use Google Fonts only to display these pages, not for analytics or advertising.
14. Children
Signal TRT is intended for adults aged 18 or over who are on testosterone replacement therapy or are actively considering it. We do not knowingly collect data from anyone under 18. If you believe a child has provided us with personal data, contact us and we will delete it.
15. Changes to this policy
We may update this Privacy Policy from time to time. Where changes are material, we will notify you in the App and, where you have provided an email address, by email, before the change takes effect. The effective date at the top of this page tells you when the current version applies from.
16. Contact
You can reach us in any of the following ways:
- Privacy queries: privacy@signaltrt.com
- General support: support@signaltrt.com
- Post: Sanderson Management Services Limited, Bryndon House, 5/7 Berry Road, Newquay, Cornwall, TR7 1AD, United Kingdom