Condition of license says you must keep the copyright intact. You can remove the "powered by machform" on your forms (the option is in the Options screen in the Admin).
https://www.machform.com/license-agreement/
Read the "restrictions" section.
Machform wrote: Restrictions
You understand and agree that you shall only use the Software in a manner that complies with any and all applicable laws in the jurisdictions in which you use the Software. Your use shall be in accordance with applicable restrictions concerning privacy and intellectual property rights.
You may not:
- Use the Software to provide services to others; such as the basis of a hosted form-building service, or any other services which is a direct competition against The Author;
- Distribute derivative works based on the Software;
- Reproduce the Software except as described in this Agreement;
- Sell, assign, license, disclose, distribute, or otherwise transfer or make available the Software or its Source Code, in whole or in part, in any form to any third parties;
- Remove or alter any copyright notices on the Software (note: You may remove the “Powered by MachForm” footer from your forms).
- Use the Software in any site which endorse unlawful manner or for any unlawful purpose.
- Use the Software in any site which contains the following materials: Pornography, Gambling Transactions or Sports Gambling Prognostication.