End-User License Agreement

We grant you a personal, non-exclusive, non-transferable, revocable license to install and use the Software on the number of machines authorized by your active subscription. Licenses are tied to a machine fingerprint at first activation; moving to a new machine takes one click and is rate-limited to one rotation per 24 hours.

• You may not copy, modify, or create derivative works of the Software.
• You may not reverse-engineer, disassemble, or attempt to extract source code or signing keys, except where applicable law expressly permits.
• You may not bypass license enforcement, share license files, or operate the Software on more machines than your seat count permits.
• You may not use the Software to provide a service-bureau, hosting, or SaaS offering to third parties without a separate agreement.

While your subscription is active, you receive updates within the current major version (e.g., 2.x) at no extra charge. Major version upgrades may require a renewed subscription term. Updates are distributed via the installer and surface as ribbon notifications.

ModelxcelPro includes cryptographic functionality (the Proof system: SHA-256 source pinning, canonical-record reviewer attestations chained into an append-only hash ledger, SHA-256 self-hashed replay and proof certificates, and for Replay Proof .mxreplay exports a sibling Ed25519-signed envelope with the public key embedded). Tamper-evident certificates, signed envelopes, and proof artifacts you export are your data and remain independently verifiable even after your license ends. Verify by recomputing the SHA-256 hash chain (using any standard cryptographic library — Node’s built-in crypto, OpenSSL, Python hashlib) or, for .mxreplay.signed envelopes, by running the zero-dependency Node verifier shipped with ModelxcelPro at tools/verify-replay/verify-replay.js; ModelxcelPro itself is not required to verify any artifact.

The Software runs locally inside Excel on your machine. Workbook contents (formulas, cell values, file paths, file names) are not transmitted to ModelXcel. The Causality ledger lives in workbook custom XML and never leaves your machine without your explicit action (e.g., emailing the workbook). Optional telemetry, when enabled, transmits only anonymized event names and durations — never workbook content.

The Software is provided "as is" without warranties of any kind. We do not warrant that the Software will be error-free or uninterrupted. To the maximum extent permitted by law, all implied warranties are disclaimed.

ModelXcel\'s aggregate liability under or relating to this EULA shall not exceed the fees you paid for the Software in the 12 months preceding the claim. Specific jurisdictional carve-outs and minimum amounts will appear in the final document following counsel review.

This EULA is effective until terminated. It terminates automatically if you breach any material provision or your subscription lapses for non-payment. On termination, you must uninstall the Software. Certificates you previously exported remain valid.

The Software contains cryptographic primitives subject to U.S. and other export control laws. You agree not to export, re-export, or transfer the Software in violation of applicable law.

This EULA is governed by the laws of ModelXcel\'s jurisdiction of incorporation (to be specified in the final document). Disputes are resolved in the competent courts of that jurisdiction unless mandatory consumer-protection law provides otherwise.