Terms of Use (Nutzungsbedingungen)

Welcome to SolverCloud, a cloud-based simulation platform ("Platform") operated by Empirisch Tech GmbH, Rennweg 88, 1030 Vienna, Austria ("we", "us", "our").

These Terms of Use ("Terms") govern your access and use of https://sandbox.numericalai.net/ ("Site") and the related online services, including uploading simulation data, and running cloud simulations ("Services").

By creating an account or using the Platform, you agree to these Terms.

1. Operator Information (Impressum Requirement)

Empirisch Tech GmbH, legally represented by the managing director Dr. Wasif Masood

Rennweg 88, 1030 Vienna, Austria

Legal Form: Limited Liability (Ltd./GmbH)

Object of the company: IT Consulting

Corporate register number: FN 566531 i

Corporate register court: Handelsgericht Wien

Member of WKO (Wirtschaftskammer Österreich)

Awarding country: Austria

Responsible for content according to § 55 RStV: Dr. Wasif Masood

2. Eligibility

To use the Platform, you must meet all of the following requirements:

• Be at least 18 years of age, or the age of legal majority in your jurisdiction
• Have full legal capacity to enter into binding agreements under applicable law
• If acting on behalf of a company, organization, or other legal entity, have the authority to bind that entity to these Terms
• Not be located in, or a resident of, any country subject to export restrictions or sanctions (including but not limited to: Cuba, Iran, North Korea, Syria, and the Crimea region)
• Not be listed on any government prohibited or restricted parties list
• Have access to the internet and equipment necessary to use the Platform

By creating an account, you represent and warrant that you meet all eligibility requirements. We reserve the right to verify your eligibility at any time and to refuse service, terminate accounts, or cancel orders if eligibility requirements are not met.

The Platform is intended for professional, academic, and research use. Users should have appropriate technical knowledge to interpret and apply simulation results responsibly.

3. Account Registration and Security

3.1 Registration Requirements. To access the Platform's services, you must create an account by providing accurate, current, and complete information including your name, email address, and any other required details. You agree to update this information promptly if it changes.

3.2 Account Security. You are responsible for:

• Maintaining the confidentiality of your login credentials
• All activities that occur under your account, whether authorized by you or not
• Notifying us immediately at support if you suspect unauthorized access or security breaches
• Not sharing your account or credentials with any third party
• Using strong, unique passwords and enabling additional security measures when available

3.3 One Account Policy. Each individual or entity may maintain only one active account. Creating multiple accounts to circumvent usage limits, bans, or to abuse promotional offers is strictly prohibited and grounds for immediate termination.

3.4 Account Suspension and Termination. We may, at our sole discretion and without prior notice, suspend or permanently terminate your account if:

• You violate these Terms of Service or any applicable laws
• You provide false, misleading, or fraudulent information
• You engage in abusive, harmful, or unauthorized use of the Platform
• Your account is used for illegal activities or export-controlled purposes
• We are required to do so by law or regulatory authority
• Your account remains inactive for an extended period (typically 24 months)

3.5 Effect of Termination. Upon account termination, whether by us or by your own deletion of the account, your right to access the Platform ceases immediately and every sandbox on the account is deleted along with its disk and contents. Any unused credits or prepaid services are non-refundable unless otherwise required by law. We may retain certain data as required for legal, tax, or audit purposes as described in section 10.4 and our Privacy Policy. For how to delete your own account, and what happens when you do, see section 10.6.

4. Scope of Services

4.1 Core Services

The Platform provides on-demand cloud sandbox virtual machines prepared for open-source computational fluid dynamics and electromagnetics work, including:

• Provisioning of single-tenant Linux virtual machines ("sandboxes") in the regions we offer
• Preinstalled open-source solvers and supporting tools, listed on our Licenses page
• Remote access to each sandbox over Remote Desktop and SSH, using credentials issued to you
• Lifecycle control — creating, starting, stopping and deleting sandboxes — through your account
• A dashboard for managing your sandboxes, credit balance, consumption and settings

A sandbox is a machine you control, not a managed simulation service. Our role is limited to building the machine image, calling Microsoft Azure's APIs to create a virtual machine from it on your instruction, and issuing you the credentials to reach it. The machine itself, and the storage attached to it, run on Azure's infrastructure. What you install on a sandbox and what you run there is your responsibility.

4.2 Service Availability

We strive to maintain high availability but do not guarantee uninterrupted service. The Platform and individual sandboxes may be temporarily unavailable due to maintenance, updates, or circumstances beyond our control, including those affecting our hosting provider. Provisioning times vary with demand and region and are not guaranteed.

5. User Content

5.1 Definition of User Content

"User Content" includes all materials you place on a sandbox or submit to us, including but not limited to:

• Solver configuration files, meshes, scripts and other simulation inputs stored on a sandbox
• Results, outputs and other data generated on a sandbox
• Software you install on a sandbox yourself
• Names you give your sandboxes and any associated metadata
• Communications sent through the Platform (support requests, feedback)

5.2 Ownership and Intellectual Property

You retain all ownership rights, intellectual property rights, and proprietary interests in your User Content. We do not claim any ownership over your simulations, models, data, or results. Your trade secrets, proprietary algorithms, and confidential information remain yours.

5.3 Our Access to Your Sandbox

We do not access the contents of your sandbox. You hold its administrator credentials, we do not log in to it, and we do not read, copy, analyse or otherwise process what you store there, by automated means or otherwise. We keep no backup of a sandbox's disk and cannot recover its contents for you.

5.4 Data Retention and Deletion

• Simulation files and results are retained while your account is active
• You may delete individual jobs and their associated data at any time via the Jobs page
• Upon account deletion, all personal, usage, and simulation data is permanently deleted
• Billing records are retained for seven (7) years after the last purchase as required by tax and accounting laws
• Anonymized, aggregated analytics data may be retained indefinitely

5.5 Prohibited Content

You represent and warrant that your User Content does not:

• Infringe any third-party intellectual property rights (patents, copyrights, trade secrets)
• Contain malicious code, viruses, malware, or security exploits
• Include unlawful, harmful, threatening, or harassing material
• Contain personal data of third parties without proper consent or legal basis under GDPR
• Violate export control laws, sanctions, or regulations (ITAR, EAR, EU dual-use)
• Relate to weapons development, nuclear technology, or controlled military applications
• Constitute classified, restricted, or government-controlled information
• Violate any applicable local, national, or international laws

5.6 Content Moderation and Removal

In compliance with the EU Digital Services Act (DSA) and our security obligations:

• Because we do not access sandbox contents, we do not scan, review or moderate what you store on a sandbox. We act on reports and on evidence available to us from infrastructure-level monitoring, such as abusive outbound network activity
• We reserve the right to suspend or terminate a sandbox or an account that violates these Terms
• We may suspend accounts pending investigation of suspected violations
• We will respond to valid legal requests and court orders regarding User Content
• We provide a mechanism for reporting illegal content through our contact form

5.7 Your Responsibility and Indemnification

You are solely responsible for your User Content and any consequences of uploading or sharing it. You agree to indemnify and hold us harmless from any claims, damages, or expenses arising from your User Content, including claims of intellectual property infringement, export control violations, or data protection breaches caused by your submissions.

6. Acceptable Use Policy

6.1 General Conduct

You agree to use the Platform only for lawful purposes and in accordance with these Terms. Your use must comply with all applicable local, national, EU, and international laws and regulations.

6.2 Prohibited Activities

You expressly agree NOT to:

• Legal violations: Use the Platform in violation of EU, German, Austrian, or any other applicable laws, including data protection (GDPR), export control, and sanctions regulations
• Security interference: Attempt to probe, scan, test, or breach the security or authentication measures of the Platform or its infrastructure
• System disruption: Interfere with, disrupt, or create an undue burden on the Platform's servers, networks, or connected systems
• Malicious content: Upload, transmit, or execute malware, viruses, trojans, ransomware, or any code designed to harm, exploit, or gain unauthorized access
• Resource abuse: Run simulations designed to consume excessive computational resources, exploit system vulnerabilities, or deny service to other users
• Reverse engineering: Decompile, disassemble, reverse engineer, or attempt to derive the source code, algorithms, or architecture of the Platform
• Circumvention: Bypass, disable, or interfere with security features, usage limits, credit systems, or access controls
• Unauthorized access: Access accounts, data, or systems belonging to other users without authorization
• Impersonation: Misrepresent your identity, affiliation, or the origin of content submitted to the Platform

6.3 Fair Use and Rate Limits

• You agree to use the Platform fairly and not to monopolize shared computational resources
• We may implement rate limits or usage caps to ensure equitable access
• Automated or scripted access to the Platform website and API (bots, scrapers) is strictly prohibited
• API access, if provided, must be used in accordance with any published API terms and rate limits

6.4 Account Integrity

• You may not share, sell, transfer, or sublicense your account or credentials to third parties
• You may not create multiple accounts to circumvent usage limits, bans, or promotional restrictions
• You may not use the Platform for competitive intelligence, benchmarking against competing services, or to develop competing products without our consent

6.5 Export Control Compliance

You acknowledge that simulation software and computational fluid dynamics tools may be subject to export control regulations. You agree not to:

• Use the Platform for purposes prohibited under US Export Administration Regulations (EAR), EU dual-use regulations, or other applicable export laws
• Submit content related to weapons development, nuclear applications, or other controlled technologies
• Access the Platform from, or transfer results to, sanctioned countries or prohibited parties

6.6 Enforcement

We reserve the right to investigate suspected violations and take appropriate action, including warning, temporary suspension, permanent termination, content removal, and reporting to law enforcement or regulatory authorities. We may cooperate with legal requests and preserve evidence of violations. Violations may result in forfeiture of unused credits without refund.

7. Simulation Output and Results

7.1 Ownership of Output

Simulation outputs, results, data files, visualizations, and reports generated from your User Content ("Simulation Output") belong to you, subject to the following conditions:

• Underlying third-party tool licenses (e.g., PyFR, released under a 3-Clause BSD License)
• Any applicable open-source licenses governing simulation tools
• Technical limitations of the Platform
• These Terms of Service

7.2 Accessing Your Results

• Simulation Output is written to the sandbox on which you ran it. It is not delivered to you through the Platform and we hold no separate copy of it
• You retrieve results yourself from the sandbox, for example with scp or another transfer method of your choosing
• Output remains on the sandbox disk for as long as that sandbox exists, including while it is stopped
• Deleting a sandbox destroys its disk and all Simulation Output on it irreversibly. We keep no backup and cannot recover it
• Retrieve your Simulation Output promptly. If your credit balance reaches zero, all of your sandboxes are deleted automatically along with any Output still on them (section 9.5)

7.3 No Warranty or Guarantee of Accuracy

Simulation Output is provided "AS IS" without warranty of any kind. We expressly disclaim all warranties regarding Simulation Output, including:

• Accuracy, correctness, or precision of numerical results
• Completeness or comprehensiveness of output data
• Fitness for any particular purpose, application, or use case
• Conformance with experimental data, theoretical predictions, or real-world behavior
• Suitability for engineering design, safety analysis, or regulatory submissions
• Absence of numerical errors, convergence issues, or computational artifacts

7.4 Limitations of Computational Simulation

You acknowledge that computational simulations are mathematical approximations subject to inherent limitations including:

• Modeling assumptions and simplifications
• Numerical discretization and truncation errors
• Mesh resolution and quality effects
• Boundary condition approximations
• Turbulence model limitations
• Hardware floating-point precision

7.5 Publication and Attribution

If you publish, present, or share Simulation Output in academic papers, reports, or public forums:

• You may acknowledge the use of SolverCloud and the underlying solver if appropriate
• You remain solely responsible for the accuracy and interpretation of published results
• Publication does not imply endorsement or verification by SolverCloud
• You must comply with any citation requirements of underlying open-source tools

7.6 Liability for Downstream Use

You assume all risk and liability for any downstream use of Simulation Output, including use in product design, engineering analysis, regulatory submissions, academic publications, or commercial applications. We are not liable for any damages, losses, injuries, or consequences arising from your use of, reliance on, or decisions based on Simulation Output.

8. Service Availability and Uptime

8.1 Availability Goals

We strive to maintain high availability and reliable access to the Platform. However, we do not guarantee uninterrupted, error-free, or continuous service. The Platform is provided on an "as available" basis.

8.2 Scheduled Maintenance

We may perform scheduled maintenance that temporarily limits or suspends access to the Platform. Where practicable, we will provide advance notice of planned maintenance via email or Platform notifications. Maintenance windows are typically scheduled during low-usage periods.

8.3 Unplanned Outages

Temporary outages may occur due to:

• Technical failures, hardware malfunctions, or software bugs
• Network connectivity issues or third-party service disruptions
• Security incidents requiring immediate response
• Excessive demand or resource constraints
• Updates, upgrades, or emergency patches

8.4 Force Majeure

We are not liable for any failure or delay in performance due to circumstances beyond our reasonable control, including but not limited to: natural disasters, acts of war or terrorism, pandemics, government actions, power outages, internet infrastructure failures, cyberattacks, or actions of third-party providers.

In the event of force majeure circumstances, we expressly disclaim all liability for any data loss, corruption, or destruction of User Content and Simulation Output, regardless of cause. This includes, but is not limited to, loss resulting from server failures, storage system malfunctions, security breaches, or infrastructure damage occurring during such events.

You acknowledge that maintaining independent backups of all critical data is your sole responsibility, and you waive any claims against us for data loss arising from force majeure events.

8.5 Limitation of Liability for Service Interruptions

In accordance with Austrian law (Allgemeines Bürgerliches Gesetzbuch - ABGB):

• We are not liable for damages resulting from temporary service unavailability, except in cases of gross negligence (grobe Fahrlässigkeit) or willful misconduct (Vorsatz) pursuant to §§ 1295 ff ABGB
• We are not liable for data loss during outages unless caused by our gross negligence or intentional acts (§ 1324 ABGB)
• Our liability is limited to foreseeable, typically occurring damages; liability for slight negligence (leichte Fahrlässigkeit) regarding purely financial losses is excluded to the extent permitted by law
• These limitations do not apply to damages arising from injury to life, body, or health, nor do they affect mandatory consumer protection rights under the Konsumentenschutzgesetz (KSchG)

8.6 No Compensation for Downtime

Unless otherwise agreed in a separate Enterprise service level agreement (SLA), you are not entitled to credits, refunds, or compensation for service interruptions or downtime. Compute credits are not consumed during periods when the Platform is unavailable for processing.

9. Fees, Payment, and Credits

9.1 Pricing and Taxes

Displayed Prices: All prices shown on the Platform are net prices, exclusive of Value Added Tax (VAT) or other applicable taxes.

VAT for EU Consumers (B2C): If you are an individual consumer located in the European Union, VAT will be calculated and applied at checkout based on your billing address, in accordance with EU VAT rules for digital services. The applicable VAT rate is determined by your country of residence. Stripe, our payment processor, handles VAT calculation and collection automatically.

VAT for EU Business Customers (B2B): If you are a business customer with a valid VAT identification number (VAT ID) registered in an EU member state, the reverse charge mechanism may apply. To qualify for reverse charge:

• You must provide your company name, address, and valid VAT ID during checkout
• Your VAT ID must be verifiable through the EU VIES (VAT Information Exchange System)
• A separate invoice will be issued showing the reverse charge notation
• You are responsible for self-assessing and reporting VAT in your jurisdiction

Non-EU Customers: If you are located outside the European Union, VAT generally does not apply. However, you are solely responsible for any import duties, local taxes, or fees imposed by your jurisdiction.

Invoices: Invoices are generated automatically and available through the Stripe Customer Portal accessible from your Settings page. For business invoices requiring company details, please ensure your information is complete and accurate at checkout.

9.2 Payment Processing

• Payments are processed securely through Stripe, Inc., a PCI-DSS compliant payment processor
• We accept major credit cards and other payment methods supported by Stripe
• Payment is due immediately upon purchase; credits are activated after successful payment confirmation
• We do not store your complete payment card details; this information is handled exclusively by Stripe
• You may manage your payment methods and billing history through the Stripe Customer Portal accessible from Settings

9.3 Failed Payments

If a payment fails, credits will not be activated. You may retry the payment or use an alternative payment method. We are not responsible for fees charged by your bank or payment provider for declined transactions.

9.4 Credit Usage and Expiration

• Credits are consumed by the hour for as long as a sandbox exists. A running sandbox is charged its compute rate plus a storage surcharge; a stopped sandbox is charged the storage surcharge only. Billing for a sandbox ends when you delete it
• Applicable hourly rates for each size and region are shown on the Create VM page before you confirm
• Low and zero balance: We send warning emails as your balance runs low. At €1 remaining, your running sandboxes are stopped automatically; if you do not top up and the balance reaches zero, every sandbox on your account is deleted, including stopped ones. See section 9.5
• Credit Expiration: Purchased credit hours are valid for 12 months from the date of purchase. After this period, unused credits will expire. This limitation complies with §6 KSchG and is necessary for operational planning and technical maintenance. You may contact us before expiry to request an extension in special cases.
• You will receive email notifications prior to credit expiration (typically 30 days and 7 days before expiry)
• Credits are non-transferable between accounts and cannot be exchanged for cash
• Expired credits cannot be reinstated, extended, or refunded
• Expiry has the same effect as consumption: if credits expire and your balance reaches zero as a result, your sandboxes are stopped and then deleted under section 9.5, exactly as if you had used the credits up

Important: By purchasing credits, you acknowledge and accept the 12-month expiration period. We recommend using credits promptly to avoid forfeiture.

9.5 Low and Zero Credit Balance: Automatic Stop and Deletion of Sandboxes

A sandbox costs money for as long as it exists, whether or not it is running. Stopping a sandbox releases its compute, but the machine continues to hold a managed disk, a reserved public IP address and associated infrastructure resources, and our hosting provider charges us for those hour by hour. We have no means of holding those resources open for an account that can no longer pay for them, and we do not carry that cost on your behalf. Automatic deletion at a zero balance is therefore a technical and economic necessity of the service rather than a penalty, and it is the reason we warn you in advance by email and repeat the warning before purchase and before you create a sandbox.

The two thresholds

• €1 remaining — automatic stop. When your remaining credit balance falls to €1 (or the equivalent in your billing currency), every running sandbox on your account is stopped automatically. Stopping releases the compute and sharply reduces the rate, but it does not halt billing: the sandbox continues to hold its disk and reserved public IP, which consume the remaining balance at the stopped rate. The purpose of this step is to slow that consumption and give you a window in which to top up with your data still intact
• Zero remaining — automatic deletion. If you do not top up, the stopped sandboxes consume the last of the balance and it reaches zero. At that point every sandbox on the account is deleted, together with its disk and everything stored on it. How long the window between the two thresholds lasts depends on how many sandboxes you hold and their stopped rates, so it is not a fixed period and should not be relied upon as one

Topping up at any point before deletion returns your sandboxes to normal; you may then start them again yourself. We do not restart stopped sandboxes automatically on your behalf.

By purchasing credits and by creating a sandbox, you expressly acknowledge and accept that:

• We will warn you by email at your registered address before it comes to this, and you can avoid deletion entirely by topping up in response to those warnings
• The automatic stop at €1 will interrupt any simulation that is running at that moment, and unsaved or in-memory work may be lost as a result
• Deletion is triggered by your balance reaching zero and applies to every sandbox on the account, running and stopped alike
• Stopping a sandbox does not protect it from deletion; only maintaining a positive credit balance does
• All User Content and Simulation Output held on the affected sandboxes is destroyed with them and cannot be recovered by us or by you
• Deletion may occur at any time once the balance is exhausted, including outside business hours and while a simulation is running, and may interrupt work in progress
• Credits expiring under section 9.4 will also bring your balance to zero and will trigger deletion on exactly the same terms
• We are not liable for any loss of data, work, time or results arising from deletion triggered by a zero credit balance, save where liability is mandatory under Austrian law

Your responsibility. You are responsible for monitoring your credit balance and topping up in good time. The Dashboard shows your remaining credits, your current hourly burn rate across all sandboxes, and an estimate of how long your balance will last at that rate. We also send low-balance warning emails to your registered address as the balance falls, so that you have the opportunity to top up before any sandbox is deleted. Those warnings are sent to the address held on your account, and it is your responsibility to keep that address current and reachable; we cannot control whether your mail provider delivers, filters or discards them, and a warning that you do not receive for reasons outside our control does not postpone deletion.

How to protect your work. Copy anything you need off a sandbox well before your balance runs low, and delete sandboxes you have finished with so that they stop consuming credits in the first place.

9.6 Refunds and Cancellations

Our refund and cancellation policies comply with EU and Austrian/German consumer protection laws:

• If you are a consumer residing in the EU, you have the right to withdraw from your purchase within 14 days under the EU Distance Selling Regulations (see Section 16 – Consumer Rights).
• Refunds for unused simulation credits may be requested during the withdrawal period, provided the service has not been partially or fully consumed.
• If you expressly request that the service begin during the 14-day withdrawal period, you acknowledge that your right of withdrawal is lost once the service has been fully performed or partially consumed. Any simulation hours already used are non-refundable.
• Subscriptions may be cancelled at any time and will remain active until the end of the current billing period.
• All refund and cancellation requests must be submitted through the contact form available under Account Settings.

9.7 Promotion Codes and Discounts

Promotional codes, discounts, or special offers are subject to their specific terms and conditions. Promotions may not be combined unless explicitly stated. We reserve the right to modify or discontinue promotions at any time. Abuse of promotional offers may result in account suspension.

10. Data Storage, Retention, and Deletion

10.1 Storage of User Content

Your User Content and Simulation Output are stored on the disk attached to the sandbox you place them on. That disk is provisioned and operated by Microsoft Azure, not by us, and we hold no copy of it. The storage is not free: it is billed as part of the hourly rate for that sandbox, including while the sandbox is stopped, as described in section 9.

10.2 Your Backup Responsibility

YOU ARE SOLELY RESPONSIBLE FOR MAINTAINING BACKUPS OF YOUR DATA.

While we implement reasonable security and redundancy measures, you should:

• Copy anything important off a sandbox promptly — we hold no backup of its disk
• Act on our low-balance warning emails, and copy your data off before your credit balance reaches zero — sandboxes are deleted automatically once it does
• Maintain your own authoritative copies of case files, meshes and results
• Not rely solely on the Platform for long-term archival storage
• Export critical data before account deletion or extended inactivity

10.3 Data Deletion Triggers

Your data may be deleted under the following circumstances:

• User-initiated deletion: When you delete a sandbox from the My VMs page, or delete your account from Settings (section 10.6). Deleting a sandbox destroys its disk and everything on it irreversibly
• Zero credit balance: When your credit balance reaches zero, whether through consumption or expiry. All sandboxes on the account — running and stopped — are then deleted automatically, together with their disks and everything stored on them, as described in section 9.5. Warning emails are sent to your registered address beforehand, and running sandboxes are stopped automatically once only €1 remains
• Account inactivity: Accounts inactive for 24 months or more may be subject to data cleanup after notice
• Account termination: Upon account closure (voluntary or due to Terms violation), all associated data is deleted
• GDPR deletion request: Upon valid exercise of your right to erasure under Article 17 GDPR
• Legal requirement: If required by court order or regulatory directive

10.4 Retention Periods

• Sandbox contents: Retained on the sandbox's disk for as long as that sandbox exists, including while it is stopped; destroyed when the sandbox is deleted, when your credit balance reaches zero (section 9.5), or when the account is terminated
• Account information: Deleted upon account closure, subject to legal retention requirements
• Billing records: Retained for seven (7) years after the last transaction as required by Austrian tax and accounting law (Bundesabgabenordnung - BAO, Unternehmensgesetzbuch - UGB)
• Security logs: May be retained for up to 12 months for fraud prevention and security purposes
• Anonymized analytics: May be retained indefinitely in aggregated, non-identifiable form

10.5 Deletion Process

Upon deletion:

• Data is marked for deletion and removed from active systems
• Backup copies of platform records (account and operational data) may persist for up to 30 days before complete removal. This does not apply to sandbox disks: we hold no backup of those, so their contents are gone the moment the sandbox is destroyed
• Deletion is permanent and irreversible; data cannot be recovered
• You will receive confirmation of account deletion via your registered email

10.6 Deleting Your Account

You may delete your account at any time from the Settings page. You will be asked to type your own email address to confirm; the request is rejected if it does not match the account you are signed in to, so the feature cannot be used against anyone else's account.

Deletion happens in two stages. An account that still owns sandboxes cannot be removed until those sandboxes are torn down, because each one holds infrastructure that must be released. When you confirm, we first delete every sandbox on the account, then remove the account itself. Tearing down a sandbox takes several minutes, and the Platform shows you the progress of each machine while it runs.

Deleting your account permanently removes:

• Every sandbox on the account, its disk, and all User Content and Simulation Output stored on it
• Your user profile and account information
• Your job history, provisioning logs and saved preferences
• Any credits remaining on the account, which are forfeited under section 3.5 and are neither refundable nor transferable

What we are required to keep. Invoices and billing records are retained for seven (7) years after your last transaction, as Austrian tax and accounting law requires (Bundesabgabenordnung – BAO, Unternehmensgesetzbuch – UGB). They are kept for that purpose alone and are not used for anything else. This is the one exception to the deletion described above; see section 10.4 and our Privacy Policy.

If deletion is interrupted. If you close the Platform or lose your connection while sandboxes are still being torn down, those sandboxes are still deleted — the process continues on our side. Your account, however, is not removed. Sign in again and repeat the request to complete it. Repeating the request is safe: it resumes the teardown already in progress rather than starting a second one.

Copy anything you wish to keep off your sandboxes before you begin. Account deletion is irreversible, we hold no backup of sandbox disks, and we cannot restore an account or its contents once the process has completed. You will receive confirmation at your registered email address.

10.7 No Liability for Data Loss

We are not liable for data loss resulting from your failure to maintain backups, user-initiated deletions, automatic deletion of sandboxes following a zero credit balance (Section 9.5), account inactivity, or circumstances described in Section 8 (Service Availability). Liability for data loss due to our gross negligence or willful misconduct is governed by Austrian law (§§ 1295 ff ABGB).

In the event of force majeure circumstances, we expressly disclaim all liability for any data loss, corruption, or destruction of User Content and Simulation Output, regardless of cause. This includes, but is not limited to, loss resulting from server failures, storage system malfunctions, security breaches, or infrastructure damage occurring during such events.

You acknowledge that maintaining independent backups of all critical data is your sole responsibility, and you waive any claims against us for data loss arising from force majeure events or any other circumstances beyond our reasonable control.

11. Intellectual Property Rights

11.1 Platform Ownership

The Platform, including all software, source code, algorithms, user interface designs, graphics, documentation, APIs, and all related intellectual property ("Platform IP") is owned by Empirisch Tech GmbH and is protected by Austrian, EU, and international copyright, trademark, patent, and trade secret laws.

11.2 Trademarks and Branding

"SolverCloud," "NumericalAI," associated logos, and all related names, marks, and slogans are trademarks or service marks of Empirisch Tech GmbH. You may not use these marks without our prior written consent, except as reasonably necessary to identify the Platform as the source of your Simulation Output.

11.3 Limited License to Use Platform

Subject to these Terms, we grant you a limited, non-exclusive, non-transferable, revocable license to access and use the Platform solely for your internal business, research, or educational purposes. This license does not include:

• Any right to sublicense, resell, or redistribute access to the Platform
• Permission to use the Platform to provide services to third parties
• Any ownership interest in the Platform IP

11.4 Prohibited Activities

You expressly agree NOT to:

• Copy, reproduce, modify, adapt, or create derivative works of the Platform or any component thereof
• Reverse engineer, decompile, disassemble, or attempt to derive source code, algorithms, or data structures from the Platform
• Remove, alter, or obscure any copyright notices, trademarks, or proprietary legends
• Use automated tools to scrape, extract, or copy Platform content or data
• Attempt to bypass, disable, or circumvent any security, licensing, or access control measures
• Use the Platform to develop competing products or services
• Sublicense, rent, lease, or lend your access to third parties

11.5 Your Content

As stated in Section 5, you retain all intellectual property rights in your User Content and Simulation Output. Nothing in these Terms transfers ownership of your proprietary data, models, or results to us.

11.6 Feedback and Suggestions

If you provide feedback, suggestions, ideas, or recommendations regarding the Platform ("Feedback"), you grant us a perpetual, irrevocable, worldwide, royalty-free license to use, modify, and incorporate such Feedback into the Platform without obligation or compensation to you. You waive any moral rights in such Feedback.

11.7 Copyright Infringement Claims

If you believe that content on the Platform infringes your copyright, please contact us via the Settings contact form with: (a) identification of the copyrighted work, (b) identification of the allegedly infringing material, (c) your contact information, and (d) a statement of good faith belief that the use is unauthorized. We will respond in accordance with applicable Austrian and EU law.

12. Third-Party Software and Services

12.1 Simulation Tools

The Platform utilizes third-party simulation software, including:

• Solvers and tools: Each sandbox image includes open-source solvers and supporting tools developed and licensed by third parties. The complete list, together with each project's licence, copyright holder and source, is published on our Licenses page and forms part of these Terms by reference.
• Additional solvers and libraries as may be added to the Platform, which will be reflected on that page

You are responsible for complying with all applicable third-party license terms when using Simulation Output for publication, commercial purposes, or redistribution.

12.2 Third-Party Service Providers

The Platform integrates with third-party service providers including:

• Stripe, Inc.: Payment processing and billing management
• Cloudflare, Inc.: Security, bot protection (Turnstile), and content delivery
• Microsoft Azure: Hosting of sandbox virtual machines and platform infrastructure

Your use of the Platform constitutes acceptance of these providers' terms of service and privacy policies. We are not responsible for the actions, policies, or practices of third-party providers.

12.3 Open Source Components

The Platform may include open-source software components subject to their respective licenses (e.g., MIT, BSD, Apache 2.0, GPL). A list of open-source components and their licenses is available upon request. Nothing in these Terms restricts your rights under applicable open-source licenses.

12.4 No Warranty for Third-Party Components

Third-party software and services are provided "AS IS" without warranty. We do not guarantee:

• Accuracy or reliability of third-party simulation tools
• Continued availability of third-party services
• Compatibility with your specific use case
• That third-party components are free from defects or security vulnerabilities

12.5 Attribution and Citation Requirements

Required Attribution: When publishing, presenting, or distributing Simulation Output in the following contexts, you must provide attribution to SolverCloud:

• Academic papers, journal articles, theses, and dissertations
• Conference presentations and scientific posters
• Technical reports and white papers
• Commercial deliverables provided to clients or customers
• Marketing materials, case studies, or promotional content
• Any context where simulation methodology is described

Suggested Citation Format:

"Simulations performed using SolverCloud (https://sandbox.numericalai.net)."

Requested Attribution: For informal sharing on social media platforms (LinkedIn, Twitter/X, etc.), we request but do not require that you acknowledge SolverCloud when sharing simulation results, visualizations, or insights generated using the Platform. A simple mention or tag is appreciated and helps support our community.

Prohibited Misrepresentation: You may NOT:

• Claim that SolverCloud, Empirisch Tech GmbH endorses your work, conclusions, or organization
• Suggest official partnership or affiliation without written agreement
• Remove or obscure any attribution, watermarks, or metadata embedded in outputs
• Misrepresent the origin of simulation results

13. Export Control and Restricted Use

13.1 Export Control Regulations

The Platform, including simulation software and generated results, may be subject to export control laws and regulations, including:

• EU Dual-Use Regulation (EU) 2021/821
• Austrian Foreign Trade Act (Außenwirtschaftsgesetz - AußWG)
• U.S. Export Administration Regulations (EAR), where applicable
• International Traffic in Arms Regulations (ITAR), where applicable
• EU and UN sanctions regimes

13.2 Prohibited Applications

You expressly agree NOT to use the Platform or any Simulation Output for:

• Weapons development: Design, development, production, or testing of nuclear, chemical, biological, or conventional weapons, missiles, or delivery systems
• Military applications: Defense systems, military vehicles, ordnance, or other military end-uses without proper authorization
• Nuclear activities: Nuclear weapons programs, uranium enrichment, plutonium processing, or unsafeguarded nuclear facilities
• Dual-use technologies: Applications listed in Annex I of EU Regulation 2021/821 without appropriate export licenses
• Surveillance systems: Mass surveillance, human rights violations, or repression technologies
• Sanctioned parties: Any activities involving sanctioned individuals, entities, or countries

13.3 Sanctioned Countries and Parties

You may not access the Platform from, or transfer any results or technology to, countries subject to comprehensive sanctions, including but not limited to:

• North Korea (DPRK)
• Iran
• Syria
• Cuba
• Crimea, Donetsk, and Luhansk regions
• Any other countries or regions subject to EU, UN, or applicable sanctions

You must not provide access to, or share results with, any individual or entity listed on EU, UN, or other applicable sanctions or denied party lists.

13.4 User Representations and Warranties

By using the Platform, you represent and warrant that:

• You are not located in, or a national or resident of, any sanctioned country
• You are not listed on any sanctions or denied party list
• You will not use the Platform for any prohibited end-use
• You will obtain all required export licenses or authorizations before any controlled transfer
• You will notify us immediately if you become aware of any potential export control violation

13.5 Consequences of Violation

Violation of export control laws or this Section 13 may result in:

• Immediate account suspension or termination without notice
• Forfeiture of all credits and data without refund
• Reporting to relevant authorities (Austrian, EU, or international)
• Civil and criminal penalties under applicable law
• Liability for all damages, fines, and legal costs incurred by us

13.6 Our Right to Restrict Access

We reserve the right to screen users and transactions, restrict access from certain jurisdictions, require additional documentation, and refuse service to any user we reasonably believe may violate export control laws, in our sole discretion and without liability.

14. EU Consumer Rights

14.1 Right of Withdrawal (Widerrufsrecht)

Under the EU Consumer Rights Directive (2011/83/EU) and Austrian FAGG (Fern- und Auswärtsgeschäfte-Gesetz), you have the right to withdraw from this contract within fourteen (14) days without giving any reason. The withdrawal period expires 14 days from the day of contract conclusion (i.e., date of purchase).

To exercise your right of withdrawal, you must inform us of your decision by a clear statement using the contact form available under Account Settings.

14.2 Exception for Digital Services

As stated in Section 9.6, your right of withdrawal expires once you have:

• Explicitly consented to immediate performance of the service before the withdrawal period expires, AND
• Acknowledged that you will lose your right of withdrawal once the service is fully performed

For simulation credits, this means once you have consumed credits by running simulations, those consumed credits are non-refundable. Unused credits remain subject to the 14-day withdrawal right.

14.3 Effects of Withdrawal

If you withdraw from this contract, we shall reimburse all payments received from you, minus the value of any services already consumed, without undue delay and no later than fourteen (14) days from the day we receive your withdrawal notice. We will use the same payment method you used for the original transaction unless you have expressly agreed otherwise.

15. Privacy, Data Protection & GDPR Compliance

15.1 Legal Framework

We process personal data in accordance with:

• EU General Data Protection Regulation (GDPR - Regulation 2016/679)
• Austrian Data Protection Act (Datenschutzgesetz - DSG)
• EU ePrivacy Directive (2002/58/EC) regarding cookies and electronic communications
• Our Privacy Policy, available here

15.2 Exercising Your Rights

To exercise any of your data protection rights:

• Use the contact form in your Settings page
• For account deletion: Use the "Delete Account" feature in Settings

We will respond to your request within 30 days, as required by GDPR. We may request identity verification before processing your request. For full details on how we handle your data, please review our Privacy Policy.

16. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, EMPIRISCH TECH GMBH AND ITS OFFICERS, DIRECTORS, EMPLOYEES, AGENTS, AND LICENSORS DISCLAIM ALL LIABILITY FOR ANY DAMAGES, CLAIMS, OR LOSSES ARISING FROM OR RELATED TO YOUR USE OF THE PLATFORM, SIMULATION OUTPUT, OR ANY SERVICES PROVIDED.

This includes, without limitation:

• Any direct, indirect, incidental, special, consequential, or punitive damages
• Loss of profits, revenue, data, goodwill, or business opportunities
• Incorrect, incomplete, or misleading simulation results
• Any decisions, designs, or actions based on Platform outputs
• Service interruptions, data loss, or security breaches
• Third-party claims arising from your use of outputs

YOU EXPRESSLY ACKNOWLEDGE THAT YOUR USE OF THE PLATFORM IS ENTIRELY AT YOUR OWN RISK. THE PLATFORM AND SIMULATION OUTPUT ARE PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT ANY WARRANTIES OF ANY KIND.

In any event, our total aggregate liability shall not exceed EUR 100 or the amount you paid us in the three (3) months preceding the claim, whichever is less.

You agree to fully indemnify and hold harmless Empirisch Tech GmbH from any claims, damages, and expenses arising from your use of the Platform or any outputs generated.

17. Indemnification

17.1 Your Indemnification Obligations

You agree to indemnify, defend, and hold harmless Empirisch Tech GmbH, its parent companies, subsidiaries, affiliates, officers, directors, employees, agents, licensors, and service providers from and against any and all claims, damages, losses, liabilities, costs, and expenses (including reasonable attorneys' fees and court costs) arising out of or related to:

• Your access to or use of the Platform or Simulation Output
• Your User Content, including any claims of intellectual property infringement
• Your violation of these Terms of Service or any applicable laws or regulations
• Your violation of export control laws, sanctions, or restricted use provisions
• Your reliance on or implementation of Simulation Output without independent verification
• Your use of Simulation Output in regulated, high-risk, or safety-critical applications
• Any products, services, or systems you develop using Simulation Output
• Any third-party claims resulting from your actions or omissions
• Your breach of any representations or warranties made in these Terms
• Any unauthorized access to or use of the Platform through your account

17.2 Defense and Control

We reserve the right, at our own expense, to assume the exclusive defense and control of any matter subject to indemnification by you. In such case, you agree to cooperate with our defense of such claim and provide all reasonably requested assistance at your expense.

17.3 Notification

We will provide you with prompt written notice of any claim for which we seek indemnification. However, failure to provide timely notice shall not relieve you of your indemnification obligations except to the extent you are materially prejudiced by such delay.

17.4 Survival

Your indemnification obligations under this Section shall survive termination or expiration of these Terms and your use of the Platform.

18. Modifications to Terms and Services

18.1 Right to Modify Terms

We reserve the right to modify, update, or replace these Terms of Service at any time at our sole discretion. Changes may be made for any reason, including but not limited to:

• Legal or regulatory compliance requirements
• Changes in applicable laws (GDPR, export controls, etc.)
• Security or operational improvements
• New features, services, or pricing changes
• Clarification of existing provisions

18.2 Notification of Changes

For material changes, we will provide notice by:

• Posting the updated Terms on the Platform with a new "Last Updated" date
• Sending an email notification to your registered email address
• Displaying a prominent notice upon login

For non-material changes, posting updated Terms on the Platform shall constitute sufficient notice. It is your responsibility to review the Terms periodically.

18.3 Acceptance of Changes

YOUR CONTINUED USE OF THE PLATFORM AFTER THE EFFECTIVE DATE OF ANY CHANGES CONSTITUTES YOUR ACCEPTANCE OF THE MODIFIED TERMS. IF YOU DO NOT AGREE TO THE UPDATED TERMS, YOU MUST STOP USING THE PLATFORM IMMEDIATELY.

18.4 Modifications to the Platform

We may at any time, without notice or liability:

• Modify, update, or discontinue any Platform features, tools, or services
• Adjust security measures, sandbox images, or the software preinstalled on them
• Modify pricing, hourly rates, or credit packages
• Impose usage limits, rate limits, or access restrictions

18.5 No Obligation to Maintain

We have no obligation to maintain, support, or update any feature of the Platform. We may suspend or terminate the Platform entirely at our discretion, subject to providing reasonable notice where practicable and honoring any prepaid credits as required by applicable consumer protection laws.

18.6 Notifications – Best Effort Basis

All notifications generated by the Platform, including but not limited to:

• Credit expiration warnings and reminders
• Account status updates and security alerts
• Planned maintenance announcements
• Terms of Service or Privacy Policy updates
• Simulation completion or failure notifications
• Billing confirmations and payment receipts
• Newsletter and promotional communications

are provided on a "best effort" basis only. We do not guarantee the delivery, timing, or receipt of any notification. Notifications may be delayed, filtered by spam systems, blocked by email providers, or fail to reach you for reasons beyond our control.

YOU ARE SOLELY RESPONSIBLE FOR:

• Maintaining a current, valid email address in your account settings
• Configuring your email settings to receive messages from our domain
• Regularly checking your account dashboard for important updates
• Monitoring your credit balance and expiration dates directly in the Platform
• Reviewing the Platform periodically for Terms or service changes

Failure to receive a notification does not relieve you of any obligation under these Terms, does not extend any deadlines (including credit expiration), and does not entitle you to any refund, credit, or compensation. We expressly disclaim all liability for any losses, damages, or missed deadlines resulting from undelivered or delayed notifications.

19. Governing Law, Jurisdiction & Dispute Resolution

19.1 Governing Law

These Terms and any disputes arising out of or relating to them or the Platform shall be governed by and construed in accordance with the laws of the Republic of Austria, without regard to its conflict of laws principles. The United Nations Convention on Contracts for the International Sale of Goods (CISG) is expressly excluded.

If you are a business, entrepreneur, or professional (Unternehmer within the meaning of § 1 KSchG), you agree that:

• The exclusive place of jurisdiction for all disputes shall be the competent courts of Vienna, Austria
• We retain the right to bring proceedings in any other court of competent jurisdiction
• You waive any objection to venue or inconvenient forum in Vienna

19.2 Class Action Waiver

To the maximum extent permitted by law, you agree that any dispute resolution proceedings will be conducted only on an individual basis and not in a class, consolidated, or representative action. If this waiver is found unenforceable, the remainder of this Section remains in effect.

19.3 Time Limitation

Any claim or cause of action arising from or relating to these Terms or the Platform must be filed within one (1) year after such claim arose, or it shall be permanently barred. This limitation does not apply where prohibited by applicable law.

20. Contact Information

20.1 Company Details

Empirisch Tech GmbH
Rennweg 88
1030 Vienna, Austria

Commercial Register: FN 566531 i
Commercial Court: Handelsgericht Wien
VAT ID: ATU 776 77 257

20.2 Contact Channels

• Please use the contact form under Settings when logged in for all inquiries

20.3 Response Times

We aim to respond to inquiries within:

• General inquiries: 3 business days
• Technical support: 72 hours on business days
• Data protection requests: 30 days (as required by GDPR)
• Legal notices: 14 business days

20.4 Language

These Terms are provided in English. In case of any translation, the English version shall prevail. Support is available in English and German.