[vbezhenar]

Because Whatsapp abuses contacts. I tried to send a message to someone without adding him to my contacts, but I did not find a way to do so in iOS. I had to add that number to my contacts and allow whatsapp full access to those.

[dirkt]

And it's actually this information Facebook is interested in, to build the "social graph".

The content doesn't matter, it knows who you communicate with and how often, and that's already a privacy concern (wife wants to know if husband cheats on her with someone else? and so on).

But of course the WhatsApp CEO doesn't mention this ... much easier to say "we don't look at your content" to give it the spin they need.

[dcsommer]

From the article:

DER SPIEGEL: Do you share these numbers with your parent company Facebook?

Cathcart: No, we don’t. The updated privacy policies will actually not change anything globally in our ability to share data with Facebook.

[throwaway888abc]

How about hashed identifier derived from phone number ?

[NicoJuicy]

Https://wa.me/+(country code)(phone number)