1. One who knows of an individual who wants to start a partnership with another, it is permitted to tell him that the fellow is a bad person and might cause him harm, when the required conditions are met [A. He is certain of the harm. B. He must not exaggerate. C. His intention is for a constructive purpose. D. There is no other way to effect a solution. G. The report will not cause the subject any harm, which is not sanctioned by Torah law].
2. Once they have already started a partnership, it is permitted to tell him, on condition that he won’t cause hurt to his partner, for example, he won’t break up the partnership, but only take care not to be harmed.

3. It is forbidden to advise one’s friend to start a partnership with someone, if he knows that it can cause him harm.