Brown has been on the books of the Glasgow giants since the summer of 2007 when he joined from Hibernian for a transfer fee reported by The Guardian to be worth £4.4 million.
The 32-year-old midfielder has established himself as one of the best players at Celtic and is one of the best footballers in the Scottish Premiership.
There have been some injury concerns over the Scotland international in recent years, but the former Hibernian star is fully fit now and has been playing well this season.
Brown’s current contract with Celtic runs out in the summer of 2019, according to Transfermarkt.co.uk, and he has suggested that he wants to carry on playing for as long as he can.
The Celtic midfielder has also opened up on his uncertainty when Brendan Rodgers took over in the summer of 2016.
Former Liverpool and Swansea City manager Rodgers was appointed the Celtic manager in the summer of 2016 following the departure of Ronny Deila.
Brown told The Daily Record: “When the manager came in, I felt I was in the last chance saloon.
“I had two years left and thought to myself: ‘I will see how it goes – if I play I play and if not then I will have given it everything I had.’
“But I’m enjoying every single moment now and I want to keep going as long as I can.”