End User License Agreement (EULA)

Acceptance of This Agreement

This End User License Agreement ("EULA" or "Agreement") is a legally binding agreement between you and Surkyl ("we," "us," or "our") governing your use of the MueSync desktop application, plugins, and related software (collectively, the "Software").

By installing, copying, or otherwise using the Software, you agree to be bound by this Agreement. If you do not agree, do not install or use the Software.

This EULA supplements our Terms of Service, Privacy Policy, Acceptable Use Policy, and Licensing Terms. In the event of a conflict between this EULA and the Terms of Service, the Terms of Service shall prevail for online services and this EULA shall prevail for the desktop Software.

Core Principles

Our licensing model is built on transparency and good faith. The following principles apply to all licenses:

• Perpetual licenses are only for local features. If a feature requires cloud processing (such as AI stem separation), the perpetual license grants access to the feature — but cloud resources require an active subscription or purchased credits.
• We do not promise what we cannot sustain. Features with ongoing infrastructure costs cannot be offered as perpetual or unlimited.
• Good faith is mutual. We offer flexibility (unlimited devices, grace periods, generous quotas) because we trust our users. In return, we expect these systems to be respected, not exploited.

License Grants

Subject to your compliance with this Agreement, Surkyl grants you a limited, non-exclusive, non-transferable license to use the Software under one or more of the following license types. For complete details on each license type, see our Licensing Terms.

Perpetual License

Acquired via a one-time purchase. Grants permanent ownership of the purchased software version. Includes a time-limited update entitlement based on purchase price. Does not include cloud services — those require an active subscription or credits.

Subscription License

Acquired via monthly or yearly subscription to a specific plugin. Grants access to the latest version while the subscription is active. After 12 continuous paid months, you earn a perpetual fallback license locked to the version available at that point.

Plan-Bundled License

Included with qualifying subscription plans (Starter, Pro, Star). Access is available while subscribed to the qualifying plan tier. Downgrading may result in loss of access to certain bundled features. No fallback license is earned for plan-bundled features.

Installment License (EMI)

Acquired via monthly installment payments over a chosen tenure. Grants access while payments are current. Upon completion of all payments, converts to a perpetual license. See Payment Terms for failure handling.

License Priority

When you hold multiple licenses for the same feature, the most favorable license applies: Perpetual > Fallback > Subscription > Plan-Bundled > Installment.

License Components

Your license consists of separate, independently modifiable components:

1. Core License Grant

Your right to use the Software. Perpetual for one-time purchases; term-limited for subscriptions. The core license grant cannot be revoked except for material breach of this Agreement.

2. Update Entitlement

Your right to receive software updates. Time-limited: 1 year ($0–$49 purchases), 2 years ($50–$99), or 3 years ($100+). Can be extended via upgrade purchase or active subscription.

3. Support Entitlement

Your right to receive technical support. Matches your update entitlement period. Subject to our current Support Policy, which may change. Support is not perpetual, even for perpetual licenses.

4. Cloud Services

Access to cloud-based features including AI processing, cloud storage, and synchronization. Not included in perpetual licenses. Requires an active subscription or top-up credits.

Cloud Services & Quotas

Cloud-based features operate on a quota system. Full details are available in our Licensing Terms.

• Each subscription plan includes a monthly processing quota that resets each billing cycle
• Subscription quota does not roll over
• At the quota limit, processing is blocked (no overage charges)
• Credit-based top-ups (stems, AI) never expire and stack across purchases
• Storage top-ups expire with the billing period (monthly or yearly add-on)
• The system consumes subscription quota first, then top-up credits

Restrictions

You may not, and you agree not to:

License Restrictions

• Share, sell, transfer, sublicense, rent, or lend your license or license keys to any third party
• Use the Software on devices not owned or controlled by you for the purpose of sharing your license
• Create multiple accounts to exploit free tiers, trial periods, or quotas
• Exceed the seat limits of your plan by sharing credentials

Technical Restrictions

• Reverse engineer, decompile, disassemble, or otherwise attempt to derive the source code of the Software
• Bypass, disable, or circumvent any license verification, digital rights management, or security mechanisms
• Modify the Software to remove or alter license checks, telemetry, or security features
• Use cracked, pirated, or unauthorized versions of the Software

AI Model Protections

Our AI models represent significant investment and are protected as trade secrets. You may not:

• Extract, copy, or recreate AI model weights, parameters, or training data
• Reverse engineer our AI models or algorithms
• Access non-public APIs or internal systems related to AI processing
• Use the Software's output to train competing AI models

Violation of AI model protections will result in immediate termination and may result in legal action.

Devices & Seats

You may install and use the Software on unlimited devices that you own or control. This is offered in good faith. Your license is personal and non-transferable. Team plans have seat limits — each seat is for one named user.

We reserve the right to revoke licenses, invalidate keys, and terminate accounts for abuse of the device or seat policies.

Updates & Support

Updates

Subscribers receive access to the latest Software version at all times. Perpetual license holders receive free updates for their entitlement period (1–3 years based on purchase price). After the entitlement period, you may continue using your current version or purchase a major version upgrade at a loyalty discount.

Fallback licenses are locked to the version at the fallback trigger point. No further updates are provided unless you resume your subscription or purchase an upgrade.

Support

Support is provided according to our current Support Policy. Support entitlement matches your update entitlement period. After this period, support access ends unless extended support is purchased. We are not obligated to provide support indefinitely.

Termination

Termination by You

You may terminate this Agreement at any time by uninstalling the Software and ceasing all use. For subscriptions, cancellation takes effect at the end of the current billing period.

Termination by Us

We reserve the right to suspend, terminate, or deny access to our Services at our sole discretion, at any time, for any reason or no reason, with or without notice. Without limiting the foregoing, we may terminate your license if:

• You violate this Agreement or our Acceptable Use Policy
• You engage in license sharing, circumvention, or other hostile behavior
• Payment fails and is not resolved within the applicable grace period
• Required by law or legal process
• We determine, in our sole discretion, that your continued use poses a risk to our Services, other users, or our business

Immediate termination without warning is reserved for hostile behavior including license key sharing, reverse engineering, payment manipulation, circumvention of licensing systems, chargeback fraud, and AI model extraction attempts.

Effect of Termination

• Subscription licenses: Access ceases at the end of the billing period (or immediately for cause). Earned fallback licenses survive termination.
• Perpetual licenses: Survive termination except when revoked for material breach.
• Installment licenses: If terminated before completion, no perpetual license is granted. Prior payments are non-refundable.

Your Data After Termination

Upon termination, your cloud data (audio files, stems, projects) is retained for 30 days. During this period, you may request a data export by contacting [email protected]. After 30 days, all data is permanently deleted. We are not obligated to retain data beyond this period.

Your Content

You own your outputs. Stems, processed audio, and other content you create using the Software belong to you. Our license is limited to providing the Services and processing your content — we do not claim ownership of your creative work.

You are responsible for inputs. You must have the necessary rights to any content you upload or process through the Software. We are not responsible for verifying your rights to input content.

By using the Software, you grant Surkyl a limited, non-exclusive license to process your content for the purpose of providing the Services and to develop and improve our own AI models and Services. We will never sell, license, or provide your content to third parties for their model training or any other purpose. You may opt out of contributing to our model training at any time in your account settings.

Disclaimers & Limitation of Liability

THE SOFTWARE IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

We do not warrant that the Software will be uninterrupted, error-free, or compatible with all hardware or software configurations. Beta, experimental, or early access features are provided without warranty.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, SURKYL'S TOTAL LIABILITY UNDER THIS AGREEMENT WILL NOT EXCEED THE GREATER OF (A) $100 USD OR (B) THE AMOUNT YOU PAID FOR THE SOFTWARE IN THE 12 MONTHS PRECEDING THE CLAIM.

IN NO EVENT WILL SURKYL BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR ANY LOSS OF PROFITS, REVENUES, DATA, USE, OR GOODWILL.

Modification & Flexibility

Modification Rights

We may modify this Agreement with 30 days' notice via email or in-app notification. For perpetual licenses, modifications apply to support and ancillary services only — the core license grant remains unchanged. Continued use after the notice period constitutes acceptance.

Discontinuation

We may discontinue any product, feature, or licensing option at our discretion with reasonable notice. Existing license holders retain their rights under the terms in effect at the time of purchase.

Grandfathering

If we modify or discontinue a licensing option, existing license holders retain their license rights as originally granted. Grandfathered users remain subject to current support policies, system requirements, and applicable laws. Grandfathering applies to the license grant only, not to support, updates, or services beyond the originally specified periods.

Enterprise

Enterprise customers with a separate Master Service Agreement (MSA) or Enterprise License Agreement (ELA) are governed by those agreements. Where an enterprise agreement is silent, this EULA applies.

Enterprise agreements cannot override core intellectual property protections, AI model restrictions, third-party license pass-throughs, or the principle that perpetual licenses cannot include cloud services.

General Provisions

Entire Agreement

This EULA, together with our Terms of Service, Privacy Policy, Acceptable Use Policy, and Licensing Terms, constitutes the entire agreement between you and Surkyl concerning the Software.

Governing Law

This Agreement is governed by applicable federal and state laws of the United States. Disputes are subject to the arbitration provisions in our Terms of Service.

Severability

If any provision of this Agreement is found unenforceable, that provision will be limited to the minimum extent necessary, and the remaining provisions remain in full force.

No Waiver

Failure to enforce any provision of this Agreement does not constitute a waiver of that provision.

Assignment

You may not assign or transfer this Agreement without our prior written consent. We may assign this Agreement without restriction.

Export Compliance

You represent that you are not located in a country subject to U.S. government embargo and are not on any U.S. government list of prohibited or restricted parties.

Contact Information

For questions about this EULA:

• Legal inquiries: [email protected]
• Licensing questions: [email protected]
• General support: [email protected]