Depends on what you mean by "third parties social sharing." If you mean other people besides you sharing your information via social channels versus you sharing it yourself, it's almost always more effective to have other people endorsing you than for you to be bragging on yourself.
Of course, it also depends on who the third parties are. If they're respected industry experts, that's one thing. If they're well known as idiots, that's something else entirely.
Think of it this way: who would you be more inclined to think truly is a genius: someone who's been praised as a genius by someone you know personally (or know of as an industry leader) and whose opinions you value, someone who's been called a genius by a couple of random people you've never heard of, or someone who runs around bragging to anyone who will listen about how smart he is?