By checking the Terms & Conditions box you hereby certify that you are aware of the following language in the Mathcad software license agreement:

Regarding Upgraded Use: If the Licensed Software was licensed as an upgrade from a previous version, Customer must first be licensed for the Licensed Software identified by PTC as eligible for the upgrade. After installing the upgrade, Licensed Software licensed as an upgrade replaces and/or supplements the product that formed the basis of Customer's eligibility for the upgrade and Customer may no longer use the original Licensed Software that formed the basis for Customer's upgrade eligibility. You must provide your existing Mathcad product code on the billing and shipping page. If you are ordering multiple Mathcad upgrades, please separate product codes by a comma.

By checking the Terms & Conditions box and submitting your Mathcad upgrade order, the person ordering certifies and agrees that they will, in accordance with the above, no later than sixty (60) days after receipt of the upgrade, cease to use the software that forms the basis of their eligibility for the upgrade, and in no event will Customer use both the upgrade and the software that forms the basis for the upgrade (except that, during the above 60-day period, Customer may use the upgrade in a non-production environment to ensure its proper performance).