By the way, the textbook is published in ISBN, and there are only general descriptions of copyright in the textbook, and there are no special restrictions, but the actual sales operation of the company is controlled by internal channels. In addition, I have been trained in the head office and got the company training certificate, so I can start classes. During the training, the head office did not explain that the teaching method was confidential, and we did not sign a confidentiality agreement. But now I asked a friend of the head office, and he said that the teaching method of the head office is unique and has intellectual property rights, so it can't be taught privately. But as far as I know, the head office doesn't have any patents. Can I start the class?
In addition, the channel control of the head office is sometimes not strict. Although there is an exclusive agent in one region, others may get teaching materials from other regions or the head office. I just had them picked up from the head office.
Sales agents are another matter. Simply from the book itself, you can use the book without infringement.