Celtic renewed their "Old Firm" trademark with Rangers just days before claiming "we're not half of anything".

The Intellectual Property Office states that Celtic and Rangers are the registered joint owners of the terms "Old Firm" and "The Old Firm".

Just last Tuesday the term "Old Firm" was renewed by both parties. The Intellectual Property Office website states: "Trademark has been renewed on 02/03/2021."

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The "Old Firm" trademark - under number UK00002264673 - dates back to March 2, 2001 - with "The Old Firm" - given number UK0002181523A - going back to 1998.

Last night Celtic claimed they aren’t “half of anything” after Rangers branded them the “other half of the Old Firm”.

Rangers referenced their city rivals in a letter to First Minister Nicola Sturgeon. It came on the back of criticism received from the Deputy First Minister John Swinney.

Swinney said the silence from Rangers was "deafening" in response to fan gatherings over the weekend.

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Celtic's draw with Dundee United on Sunday meant that Rangers were confirmed winners of this year's Scottish Premiership, leading to gatherings of fans around the city.

In the letter to Sturgeon, Rangers chairman Douglas Park said it was disappointing that Swinney had lambasted Rangers publicly, "given the club had initiated engagment with Police Scotland, the SPFL, the Scottish Government as well as the local Member of Parliament" in recent weeks in regards to potential gatherings.

Park also made reference to the “other half of the Old Firm” when writing about similar gatherings outside Parkhead last year.

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He said: “Police intelligence indicated that some fans would congregate in groups given the fact that this is not only a historic achievement but due to the behaviour from the other half of the Old Firm outside Parkhead in December. It would have been a lack of leadership to not proactively engage on this matter.”

Celtic responded with a statement of their own, which read: "Celtic Football Club Statement: We’re not half of anything... Not our problem."