Make the other side think that they have discovered important “top secret” information. Feed them false information to throw them off track. Leave “important” documents lying around so that they will find them.
Getting the other side to do something that they are not really supposed to do can give you an advantage if the way they have obtained the information is unethical, possibly even criminal, and not even true! Catch them attempting to reveal the information and they will likely feel so ashamed that they will comply with your terms of the negotiation without question.
Example
An actor is in negotiations for a leading blockbuster role. The movie-star has been out of work for so long, that the studio thinks they can get him for a rock-bottom deal. Their initial offers are insulting. The actor and his agent formulate a plan to ensure that he will earn his worth.
In the next negotiation, the agent abruptly interrupts the discussion and says he has to have a talk with his client. They rush out of the room, “accidentally” leaving their notes behind. On it the agent has listed recent “offers” the agent has received to work on other movies. The offers are all much higher than what the studio has presented so far. If the actor is getting proposals for this much, well then he must be worth it.
When the actor and agent return, the studio executives change their tone and attempt to charm and persuade the actor to sign on with their production for more than what anyone else was “offering”.
