The 20-year-old has impressed for City this season, earning international recognition with Republic of Ireland's Under-21 side along the way.
And Caulfield says a host of Premier League and Championship sides have had the full-back scouted, with two bids received - both of which were rejected. Negotiations, though, remain ongoing with one club.
"A lot of teams have watched him, but it's a business deal and it isn't up to Cork City to name the clubs involved," Caulfield told reporters.
"Everyone knows who has watched him; Arsenal have, Hull have, we've realised that Manchester United have watched him, Tottenham, Everton and Villa have watched him.
"They've all had direct club employees to look at him as opposed to some of the championship clubs, who'd have an agent saying he's representing them.
"The official situation is that we received two bids and both have been rejected. One of the clubs has come back to us and we’re in negotiations with them but there's still quite a bit of work to do.
"Do I think that he’ll be gone across channel in the next couple of weeks? I believe that he will, and we have to make sure that we get the proper deal and Brian does too.
"What we have to try and do is a structured deal that if he plays international football or moves on elsewhere, we get rewarded. That’s probably what you have to look at."