Celtic were even interested, but it appears the 17-year-old is committing to Boro.
He is set to sign a new long term deal with the club, which will keep him there for at least the next three years.
Boro's academy manager Craig Liddle said via The Sun: "We're delighted Calum has signed a professional contract.
"He's shown great application and has a real good work ethic.
"He has a long way to go and a lot to learn, but this is another step on the ladder for him and his continued development."