in the concept of land surveying, Can one have a “boundary by occupation”?

Yes, in land surveying, it is possible to have a boundary by occupation. This concept is known as "adverse possession" or "squatter's rights." Adverse possession occurs when someone occupies and uses another person's land without permission for a certain period of time, typically ten years or more, and meets specific requirements set by the law. If the requirements are met, the person who occupied the land may be able to claim legal ownership of it, creating a boundary by occupation. However, the specific requirements for adverse possession can vary depending on the jurisdiction, so it is essential to consult local laws and regulations.