At people forgetting Bad Romance and Tik Tok
Bad Romance, Tik Tok and Love the way you lie BY FAR
These 3 songs sold (9.7M, 11M and 9M ) in 2010 ALONE. They've kept selling since then. There is no chance any song after has outsold them WW.
In 2011 Rolling in the deep sold 8.2M (which was the same as Born This Way and less than the other 3)
Happy is probably going to be around 10-12M but with STREAMING included (cuz that's how IFPI works now)
and yeah Blurred Lines is also with streaming included and it's 11M at most.
And people calling songs that are not even 10M WW

WFL - No. Roar - No. DH - hah No.
Gangnam Style - No. Moves Like Jagger, Call me maybe and STIUTK are the only 3 that can compete. Maybe Rolling in the deep as well.
And let's not forget Bruno who had 2 SMASHES with 10M+ WW in a SINGLE YEAR - Granade and Just the way you are.