A more thorough explanation:

RES PUBLICAE

Res publicae is a Latin term that means "public things." In Roman and civil law, it refers to things that cannot be owned by individuals because they belong to the public. Examples of res publicae include the sea, navigable waters, and highways. These things are owned by the state and its political subdivisions as public entities.

• The sea
• Navigable waters
• Highways

These examples illustrate the definition of res publicae because they are all things that are used by the public and cannot be owned by individuals. For example, the sea is a public resource that is used for fishing, transportation, and recreation. Navigable waters are used for shipping and transportation, and highways are used for travel and commerce. Because these things are essential for the public good, they are owned by the state and its political subdivisions.