an online business contact marketplace where marketers, recruiters, and sales people can buy, sell and trade business contact informationMembers buy their way in, either through a monthly subscription fee or by providing a certain number of their contacts to the system. Yes, the currency is the contact info of your friends and colleagues.
So, if you hand me your business card, I can effectively sell that information to Jigsaw. My gain, your (through the potential for cold calls from salespeople) loss.
You almost certainly weren't thinking of my abusing the privilege in this way when you gave me your business card. But, beyond scribbling across the front a non-enforceable 'Not for Resale', there is not much you can do to stop me.
If however, you had initially provided me your contact info digitally, then you could at least be given mechanisms/syntax in order to express any restrictions you might wish to impose on me. Such restrictions could include limiting sharing, constraints on contact (e.g. don't use IM before noon), or limits on how long the info could be stored).
Such preferences would still almost certainly remain unenforceable but I could no longer claim innocence or ignorance. Importantly, neither could Jigsaw if the preferences stayed with the contact info if and when submitted there.
Identity Rights Agreements would make this possible.