Although I agree with both of the above comments,
However, I think if you are a ISP and offering to do this as a service for a "new client" that has asked to transfer over to you, then all well and good, it's just that your boss has passed the job onto you to carry out.
(Could this not just be part of establishing good customer relations by taking the task away from the client)?
On the other hand, "if" and I use the word carefully, if your boss is trying to pull a fast-one and sign-up/transfer a client to your company who does not realise whats happening until after they have been transfered, then this must not only bad practise, bordering on some sort of fraud but downright unacceptable and surely it would not take much for this type of practise to go un-noticed and appropriate action taken by the regulating bodies.
I would further to suggest, providing you make yourself and company known to the other ISP that you are applying on behalf of the person at their request then that should be sufficient.
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