In recent years 2014 and 2016 have been notable for key moves being made. In the former, Aberdeen added Shay Logan and Adam Rooney, while Celtic signed Leigh Griffiths as well as Stefan Johansen. Two years later, Patrick Roberts headed to Parkhead with Anthony Stokes moving to Hibs. John Souttar and Gary Dicker would join Hearts and Kilmarnock respectively.
In the mid-2000s Rangers made two of their most impressive signings in bringing Barry Ferguson back to the club in 2005 and signing Davie Weir in 2007.
Between then, Hearts famously, or infamously, signed 11 players in the January window as Vladimir Romanov made his mark on the squad which had been challenging Celtic for what was then the SPL title.
This window has already witnessed Ange Postecoglou make a triple swoop from the J-League, while across the city Rangers are on the cusp of breaking their record transfer sale with academy graduate Nathan Patterson who is on the verge of a reported £12million move to Premier League side Everton. A few which could rise further.
On top of that Hibs are very active in the market under new boss Shaun Maloney with Callum Davidson and St Johnstone looking to add heavily with the club bottom of the league. The likes of Hearts, Dundee United and Aberdeen will also likely make key additions.
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Between then, Hearts famously, or infamously, signed 11 players in the January window as Vladimir Romanov made his mark on the squad which had been challenging Celtic for what was then the SPL title.