"...
unless your content has been shared with others, AND [not '
or']
they have not deleted it."
But wait. What if another person's privacy settings preclude one's ability to know if people have shared my content or not, and/or whether those people deleted it?
Doesn't that place Facebook in a realm of ultimate deniability with respect to whether or not they are still in lawful possession of this implicit IP License?
Case in point:
1. I upload a scandalous and controversial image, accidentally.
2. I have a friend, who can see the album that contains the
image. [thus it is "shared"]
3. This "friend" immediately shares it. [satisfying the
requisite logical AND whereby it is simultaneously both
shared and not yet deleted by them]
4. The friend UNFRIENDS me (OH NOES!), and locks me out of
viewing anything related to their account.
5. I delete the image, believing that I am revoking the
implicit IP License.
6. Unbeknownst to me, Facebook retains an IP License by virtue
of the fact that someone else has not deleted the image.
7. Due to Facebook's policy, they are bound by their own
privacy obligations to the other user, to withhold from me
information regarding WHO still possesses the image, and
will not tell me HOW they are able to claim lawful
possession of an IP License for the image I am trying to
revoke.
8. I am stuck in the very limbo that OP is complaining about,
whereby Facebook claims to have an implicit License to
publish content, but will refuse to disclose the evidence
of who has yet to delete the image, as prove that their own
license is derived by the actions of another.
9. In theory, this other user might very well "forget" their
Facebook password (whoopsie! but innocently, and certainly
not as revenge...) and lock themselves out of their own
account. In this manner Facebook now entitles themselves to
the IP rights of this image in perpetuity, without the
potential for revocation, because thei refuse to unlock the
sharer's account without adequate proof.
So when you "share with others" (whatever that might specifically mean, according to how they've defined their user interface at that particular moment), that very action is potentially bestowing onto Facebook potentially eternal IP rights to distribute that content forever.
Like, simply by virtue of sharing, any person who then accesses the content and then re-shares it and refuses to delete it, is then acting as the de-facto rights holder from which all of Facebook's privileges are derived.
But by letting another Facebook user access your shared content, as a peer, it's not immediately clear where that peer truly derives their eternal permission to forever re-share everything they ever had access to as your friend. Why does that person possess eternal rights to share YOUR content on Facebook, simply by being listed as your friend? Where does that part come from? Isn't that behavior enabled by Facebook? And doesn't Facebook reserve the right to redefine how things are "shared" at will? So then, doesn't that mean that Facebook is enabling itself?
Doesn't it seem like there is strong potential for a conflict of interest between Facebook and the other two parties involved?