What is the most likely classification of Frank allowing Rich to use his ice fishing shack?

The classification of Frank allowing Rich to use his ice fishing shack is best identified as a license. A license in real estate specifically allows a person to enter or use another person's property for a designated purpose without transferring any ownership interest. In this case, Frank has provided permission to Rich to use the ice fishing shack, indicating that Rich has a temporary and revocable right to use the property, which is characteristic of a license.

Licenses do not create any permanent interest in the property and can typically be revoked at any time by the property owner, which aligns with the nature of the situation described. Therefore, this agreement is foundational in understanding that a license is merely permission and not a right that can be claimed by the licensee.

In contrast, an appurtenance refers to a right that is tied to the property and usually conveys with it, which is not the case here. An easement in gross involves a right to use someone else's land for a specific purpose that can be somewhat permanent, but Rich's use does not suggest that level of legal entitlement. Encroachment pertains to a situation where a property owner illegally uses part of someone else's property, which does not fit this scenario either. Therefore, the most accurate classification of Frank's permission to