Yes it has happened according to Rob Feinstein of RFVideo.com posted the following on his Facebook page
I was just informed Sting has signed a deal with WWE in the last 24 hours. I still think personally he will show up after Mania since it seems like Undertaker vs Brock is what they are aiming for. Reminds me when everyone thought Brock would debut in Miami but they waited for Raw.
There has been many reports in the last 24 hours that Sting has signed with WWE. So this time it might be true.
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