The 24-year-old midfielder, who was born on Tyneside and supported the Magpies as a boy, has signed a long-term contract after rejecting a new deal at the Stadium of Light.
Pardew said: "I'm extremely pleased to have brought Jack to Newcastle United. He's a great passer, versatile and rarely gives the ball away.
"He's also a local lad and knows exactly what playing for this club means, and at 24 years old, his best years are ahead of him, so I think he'll be a big asset to us."
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