"But....but....but ... Celtic trademarked it............"
Now this is tedium. I will repeat again... the term 'Old Firm' is a satirical , not particularly endearing nick-name give to 'Rangers,Celtic Ltd' in the early years of the 20th Century as the unholy cartel took control over Scottish football and conned their ever gullible fan base out of yet more money. Neither Celtic nor Rangers came up with the term 'Old Firm'. It is not theirs to either claim or indeed disown. They can cease to use the phrase all they want. The rest of Scottish football will know them by their actions and for us , as long as two football clubs calling themselves Celtic & Rangers exist we will call them by their collective nick-name. So please, however else you may wish to insult me, do not insult me by trying to tell me who or what 'The Old Firm' are. That is not your call (or indeed Jim Traynor's - see what I did there) to make.