Privacy policy

Last updated December 8th, 2025

This privacy notice applies to Reasoning Engine B.V., doing business as LangWatch (“we,” “us,” or “our”), and explains how and why we collect, store, use, and share your information (“process”) when you use our services (“Services”). This includes situations where you:

Visit our website at https://www.langwatch.ai, use our Cloud Service, or access any of our websites that link to this privacy notice
Interact with us in other ways, such as through sales activities, marketing communications, or events

Questions or concerns? Reviewing this privacy notice will help you understand your privacy rights and available choices. If you do not agree with the practices described here, please do not use our Services. If you have any questions or concerns, you can contact us at privacy@langwatch.ai.

Summary

This overview highlights the main points of our privacy notice. For more detailed information on any topic, you can follow the link provided with each section or use the table of contents below to navigate directly to the relevant part of the notice.

What personal data do we process?
When you visit, use, or interact with our Services, we may collect and process personal data depending on how you engage with the Services, the choices you make, and the features or products you use. You can find more details about the personal information you provide to us in the relevant section of this notice.

Do we process sensitive personal data?
No. We do not collect or process sensitive personal data.

Do we receive personal data from third parties?
No. We do not obtain personal data from third parties.

How do we use your information?
We use your information to operate, maintain, and improve our Services, communicate with you, ensure security and prevent fraud, and comply with legal obligations. Where required, we may also process your information for additional purposes with your consent. We only process personal data when we have a valid legal basis to do so. Further details are available in the section explaining how we process your information.

When and with whom do we share personal data?
We may share personal information in limited circumstances and only with specific third parties. More information about these situations and recipients is provided in the relevant section of this notice.

How do we protect your information?
We implement appropriate organizational and technical measures to safeguard your personal data. That said, no method of data transmission over the internet or electronic storage is completely secure. As a result, we cannot guarantee absolute security against unauthorized access, misuse, loss, or alteration. More details about our security practices are outlined below.

What rights do you have?
Depending on your location, applicable data protection laws may grant you certain rights in relation to your personal data. These rights are explained in more detail in the corresponding section.

How can you exercise your rights?
You can exercise your rights by submitting a data subject access request or by contacting us directly. We will review and respond to all requests in accordance with applicable data protection legislation.

Want to learn more about what we do with any information we collect? Review the privacy notice in full here below..

Table of Contents

What information do we collect?
How do we process your information?
What legal bases do we rely on to process your personal information?
When and with whom do we share your personal information?
Do we use cookies and other tracking technologies?
How do we handle your social logins?
How long do we keep your information?
How do we keep your information safe?
Do we collect information from minors?
What are your privacy rights?
controls for do-not-track features
Do we make updates to this notice?
How can you contact us about this notice?

1. What Information do we collect?

Personal information you disclose to us

**In Short:** We collect personal information that you provide to us.

We collect personal information that you voluntarily provide to us when you register on the Services, express an interest in obtaining information about us or our products and Services, when you participate in activities on the Services, or otherwise when you contact us.
Personal Information Provided by You. The personal information that we collect depends on the context of your interactions with us and the Services, the choices you make, and the products and features you use. The personal information we collect may include the following:

names
email addresses
usernames
passwords
contact preferences
billing addresses
debit/credit card numbers
phone numbers
mailing addresses

Payment Data. We may collect data necessary to process your payment if you make purchases, such as your payment instrument number, and the security code associated with your payment instrument. All payment data is stored by Stripe. You may find their privacy notice link(s) here: https://stripe.com/en-gb-de/privacy.

Social Media Login Data. We may provide you with the option to register with us using your existing third party account details, like your Google, GitHub, or other authentication account. If you choose to register in this way, we will collect the information described in the section called "How Do We Handle Your Social Logins?" below.

All personal information that you provide to us must be true, complete, and accurate, and you must notify us of any changes to such personal information.

Information automatically collected

In brief: Certain information such as your Internet Protocol (IP) address and browser or device details is collected automatically when you access our Services.

When you visit, use, or navigate our Services, we automatically collect specific technical and usage information. This data does not directly identify you (for example, it does not include your name or contact details), but it may include details such as your IP address, browser type, device characteristics, operating system, language settings, referring URLs, device name, country or general location, and information about how and when you interact with our Services.

We collect this information primarily to ensure the security and proper functioning of our Services, as well as for internal analytics, monitoring, and reporting purposes.

As with many organizations, we also use cookies and similar tracking technologies to collect certain information. For more details about how we use these technologies, please refer to our Cookie Policy.

The information we collect includes:

Log and Usage Data. Log and usage data includes service-related, diagnostic, usage, and performance information that our servers automatically collect when you access or use our Services and store in log files. Depending on how you interact with the Services, this data may include your IP address, device details, browser type and settings, and information about your activity within the Services. This can include date and time stamps, pages or files viewed, searches performed, and other actions you take, such as which features you use. Log data may also include device event information, such as system activity, error reports (sometimes referred to as “crash dumps”), and hardware settings.
Device Data. We collect information about the devices you use to access our Services, such as your computer, smartphone, tablet, or other devices. Depending on the device, this data may include your IP address (or proxy server), device and application identifiers, location data, browser type, hardware model, internet service provider or mobile carrier, operating system, and system configuration details.
Location Data. We collect location-related information about your device, which may be precise or approximate depending on the device type and its settings. The amount of location data we collect varies based on how you configure your device. For example, we may use GPS, IP address data, or similar technologies to determine your general or precise location. You can choose to prevent us from collecting location data by denying access permissions or disabling location services on your device. Please note that if you do so, certain features of the Services may not function properly or may become unavailable.

2. How do we process your information?

In brief: We use your information to operate, maintain, and improve our Services, communicate with you, ensure security and prevent fraud, and comply with legal obligations. Where required, we may also process your information for additional purposes with your consent.

We process personal information for a range of purposes, depending on how you interact with our Services, including the following:

Account creation and management. We process your information to enable you to create an account, log in securely, and keep your account functioning properly.
Service delivery. We use your information to provide and facilitate the delivery of the Services you request.
User support and inquiries. We process your information to respond to your questions, provide customer support, and resolve any issues you may experience.
Administrative communications. We may use your information to send you service-related messages, such as updates about our products and Services, changes to our terms or policies, and other administrative notices.
Order and transaction management. We process your information to fulfill and manage orders, payments, returns, and exchanges made through the Services.
Feedback and service improvement. We may process your information to request feedback and contact you regarding your use of our Services.
Security and fraud prevention. We use your information to help protect our Services, including monitoring for and preventing fraudulent or unauthorized activity.
Usage analysis and trend identification. We analyze how users interact with our Services to better understand usage patterns and improve functionality and performance.
Marketing effectiveness. We may process your information to assess the effectiveness of our marketing and promotional efforts and ensure they are relevant to you.
Protection of vital interests. In limited circumstances, we may process your information when necessary to protect an individual’s vital interests, such as to prevent serious harm.

3. What legal bases do we rely on to process your personal information?

In brief: We process your personal information only when it is necessary and when we have a valid legal basis under applicable law. This may include your consent, compliance with legal obligations, performance of a contract, protection of your rights, or pursuit of our legitimate business interests.

If you are located in the EU or the UK

This section applies to you if you are located in the European Union or the United Kingdom.

Under the General Data Protection Regulation (GDPR) and the UK GDPR, we are required to explain the legal bases on which we rely to process your personal information. Accordingly, we may process your personal information on the following grounds:

Consent. We may process your personal information when you have given us explicit permission to do so for a specific purpose. You may withdraw your consent at any time.
Performance of a contract. We may process your personal information where it is necessary to perform a contract with you, including providing our Services, or to take steps at your request prior to entering into a contract.
Legitimate interests. We may process your personal information when it is reasonably necessary to pursue our legitimate business interests, provided those interests are not overridden by your fundamental rights and freedoms. These purposes may include:
- Analyzing how our Services are used in order to improve functionality and user engagement
- Supporting and improving our marketing activities
- Detecting, diagnosing, and preventing fraud or misuse
- Understanding user behavior to enhance the overall user experience
Legal obligations. We may process your personal information where necessary to comply with our legal obligations, including cooperating with regulatory authorities or law enforcement agencies, exercising or defending legal claims, or disclosing information in connection with legal proceedings.
Vital interests. In limited circumstances, we may process your personal information where necessary to protect your vital interests or those of another individual, such as in situations involving risks to personal safety.

For the purposes of European data protection law, we generally act as the data controller with respect to the personal information described in this privacy notice, as we determine the purposes and means of the processing. This privacy notice does not apply to personal information that we process as a data processor on behalf of our customers. In those cases, the customer with whom we have entered into a data processing agreement is the data controller, and we process personal information solely on their instructions. To learn more about how our customers handle personal information, please review their respective privacy policies and direct any related questions to them.

4. When and with whom do we share your personal information?

In brief: We may share your personal information in the specific circumstances outlined below and with the categories of third parties described in this section.

We may share your personal information with third-party vendors, service providers, contractors, or agents (“third parties”) that perform services for us or on our behalf and require access to that information to carry out their work. We maintain contractual agreements with these third parties that are designed to protect your personal information. These agreements require that third parties:

Process personal information only in accordance with our instructions
Not disclose your personal information to any other organization without our authorization
Implement appropriate safeguards to protect the data they process on our behalf
Retain personal information only for the period we specify

The categories of third parties with whom we may share personal information include:

Advertising, direct marketing, and lead generation
HubSpot
Cal.com
Google Workspace
Framer
User authentication and third-party account connections
Google Authentication
GitHub
Azure Active Directory (Azure AD)
Cloud computing and infrastructure services
Vercel
Amazon Web Services (AWS)
Elastic Search
Cloudflare
User communication and support tools
Slack
Crisp
GitHub
Billing and payments
Stripe
Product analytics and metrics
PostHog, Inc
Pendo
Hotjar
Internal operations and collaboration
Notion
Google Workspace
Application monitoring and performance (internal use)
Sentry
Snyk

We may also share or transfer your personal information in connection with, or during negotiations relating to, a merger, sale of company assets, financing, or acquisition of all or part of our business by another company.

5. Do we use Cookies and other tracking technologies?

In brief: We use cookies and other tracking technologies to collect and store certain information.

We may use cookies and similar technologies, such as web beacons and pixels, to access or store information when you interact with our Services. Details about how we use these technologies, as well as how you can manage or refuse certain cookies, are explained in our Cookie Policy.

6. How do we handle social logins?

In brief: If you choose to sign up or log in to our Services using a social media account, we may receive certain information about you from that provider.

Our Services allow you to register and log in using credentials from third-party social media platforms, such as Google, Microsoft or GitHub. When you choose this option, we receive specific profile information from the relevant social media provider. The information we receive may vary depending on the provider, but typically includes your name, email address, profile image, and any other information you have chosen to make publicly available on that platform.

We use this information solely for the purposes described in this privacy notice or as otherwise clearly disclosed to you at the time of collection. Please note that we do not control and are not responsible for how third-party social media providers collect, use, or share your personal information. We encourage you to review their privacy notices to understand their data practices and to manage your privacy settings through their websites or applications.

7. How long do we keep your information?

In brief: We retain your personal information only for as long as necessary to achieve the purposes described in this privacy notice, unless a longer retention period is required by law.

We keep personal information only for the duration needed to fulfill the purposes outlined in this privacy notice, unless applicable laws require or permit a longer retention period, such as for tax, accounting, or other legal obligations. In any case, no purpose described in this notice requires us to retain your personal information for longer than one (1) month after your account has been terminated.

When we no longer have a legitimate business need to process your personal information, we will either delete or anonymize it. If immediate deletion or anonymization is not possible—for example, because the data is stored in backup systems—we will securely retain the information and restrict it from further processing until deletion becomes feasible.

8. How do we keep your data safe?

In brief: We protect your personal information using appropriate organizational and technical security measures.

We have implemented reasonable technical and organizational safeguards designed to protect the personal information we process. Despite these measures and our ongoing efforts to secure your data, no method of transmission over the internet or electronic storage can be guaranteed to be completely secure. As a result, we cannot guarantee that unauthorized third parties, such as hackers or cybercriminals, will not be able to bypass our security measures and improperly access, obtain, alter, or misuse your information.

While we take the protection of your personal information seriously, any transmission of personal data to or from our Services is done at your own risk. We recommend that you access the Services only from a secure environment.

9. Do we collect information from monitors?

In brief: We do not knowingly collect personal data from, or market our Services to, individuals under 18 years of age.

We do not knowingly collect personal information, in our role as data controller, from children under the age of 18, nor do we knowingly market our Services to them. By using the Services, you confirm that you are at least 18 years old, or that you are a parent or legal guardian providing consent for a minor dependent to use the Services.

If you believe that we may have collected personal information from a child under the age of 18, please contact us at privacy@langwatch.ai so that we can take appropriate action.

10. What are your privacy rights?

In brief: In certain regions including the European Economic Area (EEA), the United Kingdom (UK), Switzerland, and Canada you have rights that give you greater access to and control over your personal information. You may review, update, or close your account at any time.

Your privacy rights

If you are located in the EEA, UK, Switzerland, or Canada, applicable data protection laws grant you specific rights in relation to your personal information. These rights may include the ability to:

Request access to and obtain a copy of your personal information
Request correction or deletion of your personal information
Request restriction of the processing of your personal information
Request data portability, where applicable
Object to the processing of your personal information
Not be subject to certain forms of automated decision-making

You may exercise any of these rights by contacting us using the details provided in the section titled “How can you contact us about this notice?” below. We will review and respond to all requests in accordance with applicable data protection laws.

Complaints to data protection authorities

If you are located in the EEA or the UK and believe that we are processing your personal information unlawfully, you have the right to lodge a complaint with your local data protection authority or the UK data protection authority.

If you are located in Switzerland, you may contact the Federal Data Protection and Information Commissioner.

Withdrawing your consent

Where we rely on your consent whether express or implied, depending on applicable law—you may withdraw that consent at any time. For users of our Managed Cloud Services, withdrawing consent will typically require deletion of your account. You can withdraw your consent by contacting us using the details provided below or by updating your account preferences.

Please note that withdrawing consent does not affect the lawfulness of any processing carried out prior to withdrawal. Where permitted by law, it also does not affect processing based on legal grounds other than consent.

Marketing and promotional communications

You may opt out of receiving marketing and promotional communications at any time by clicking the unsubscribe link in our emails or by contacting us using the details provided below. Once you opt out, you will be removed from our marketing lists. However, we may continue to send you non-marketing communications that are necessary for the operation and administration of your account or to respond to service-related requests.

Account information

If you wish to review, update, or terminate your account at any time, you may:

Upon receiving a request to close your account, we will deactivate or delete your account and remove your information from our active systems. In some cases, we may retain certain information to prevent fraud, resolve disputes, assist with investigations, enforce our legal agreements, or comply with applicable legal requirements.

Additional information about how to delete your account is available here.

Cookies and similar technologies

Most web browsers accept cookies by default. You can usually change your browser settings to remove or reject cookies if you prefer. Please note that disabling cookies may affect the functionality or availability of certain features of our Services. For more information, please review our Cookie Policy.

If you have any questions or concerns about your privacy rights, you may contact us at privacy@langwatch.ai

11. Controls for Do-Not-Track features

Most web browsers, as well as some mobile operating systems and mobile applications, offer a Do Not Track (“DNT”) setting that allows you to indicate your preference not to have your online browsing activities monitored or collected. At present, there is no universally accepted standard for recognizing or implementing DNT signals.

As a result, we do not currently respond to DNT signals or to any other automated mechanisms that communicate a user’s preference not to be tracked online. If a standardized approach to online tracking is established in the future that we are required to follow, we will update this privacy notice to reflect that practice.

12. Do we make updates to this notice?

In brief: Yes, we may update this privacy notice from time to time to remain compliant with applicable laws.

We may revise this privacy notice periodically. Any updates will be indicated by a revised “Last updated” date, and the updated version will take effect as soon as it is made available. If we make material changes to this privacy notice, we may notify you by prominently posting a notice or by contacting you directly.

We encourage you to review this privacy notice regularly so you remain informed about how we protect your personal information.

14. How can you contact us about this notice?

If you have questions or comments about this notice, you may email us at privacy@langwatch.ai or contact us by post at:

Herengracht 551
1017BW Amsterdam
The Netherlands

15. How can you review, update, or delete the data we collect from you?

Depending on the laws that apply in your country, you may have the right to request access to the personal information we hold about you, to correct that information, or to request its deletion. To review, update, or delete your personal information, please submit a data subject access request by e-mailing your request to: privacy@langwatch.ai or support@langwatch.ai