Have a friend who makes crowns etc. for dentists. He took a job here in town working for two dentists. They hired some junior folk and had him train them and then fired him.
He tried to start his own business so they sued him with a noncompete. They claimed thousands of dentists as their territory and the judge became angry with them but in the end the noncompete crippled his ability to make a living for years.
On the flip side, I have another friend who was brought into a small town for a small branch of a medical-related practice. After awhile, he joined with the other guys in town and they started their own thing.
They actually did buy the business from the group who had brought them out, but it was a bit of a forced sale because there was no legal way for the group to stop them.
He tried to start his own business so they sued him with a noncompete. They claimed thousands of dentists as their territory and the judge became angry with them but in the end the noncompete crippled his ability to make a living for years.