I highly doubt Yahoo is selling your e-mail contacts to LI. Do you have any proof or citations? I suspect either you authorized LI in the past (and forgot it's still authorized), or your contacts have authorized LI so it's pulling in their e-mails with you, not yours.

I think you might be forgetting that by e-mailing said person, you become part of their contacts too. Should that person decide to import or sync their contacts in linkedin, a relationship between you and that person is established on their server. ie: it's an _undirected_ edge between you and your contact, which they seem to use to display stuff back to you.

no, no, no. Reddit's Razor: if a corporation could be doing something evil, they are doing that something.

These "social" big data companies have a history of doing evil (or sometimes, stepping right up to that line) and $LKND certainly isn't in business to be altruistic.

Their iphone app used to slurp up your data without authorization: http://arstechnica.com/apple/2012/06/your-iphone-calendar-is...

Furthermore:

LinkedIn: The Creepiest Social Network

https://news.ycombinator.com/item?id=5680680

LinkedIn opts 100 million users into sharing information with ads

https://news.ycombinator.com/item?id=2872030

LinkedIn is Evil

https://news.ycombinator.com/item?id=220138

I thank you for providing examples that prove my point. :) That's mostly speculation along the lines of "evil could have been done, therefore evil must have been done".