It's not known how much Forest offered for the midfielder but the bid was swiftly rejected by Boro.
It's understood the approach was made on Sunday night, just a day after Hackney categorically ruled out leaving Boro ahead of tonight's 7pm deadline, telling of his dream to captain his boyhood club to promotion this season.
Hackney has 18 months left to run on his current deal at the Riverside.
The midfielder had the opportunity to leave for Ipswich Town early in the summer window but turned down the Tractor Boys. Premier League interest then emerged late in the summer window but Boro's stance was that the 23-year-old was not for sale.
And that remains the case now.
Hackney has starred this season for Boro and scored the only goal in Saturday's 1-0 victory over Norwich, a fifth successive win for Kim Hellberg's side that took them joint top of the Championship.
After the game, Hackney said: “This is what I’ve wanted to do ever since I was a kid - play for Middlesbrough.
"And where we are in the league at the minute, as long as we just keep going, we feel confident.
“Winning promotion with Middlesbrough would mean everything to me. I don’t know how I’d be, but I know I’d be over the moon.
“That is the dream. We just take it game by game, but at the minute, the squad’s looking very good. We’ve got competition all over the place. We’ll keep working hard and see where it takes us.”
Asked directly if that meant there was no chance of him leaving Middlesbrough ahead of tonight's 7pm deadline, he said: “No. I’m really happy. The manager’s got me playing the way I enjoy playing, getting the best out of me. So yeah, I’m really enjoying it.”