According to German newspaper WAZ, Dortmund currently have approximately 154,000 officially registered members, but the Royal Blues' numbers have swollen recently to reach 156,110, taking them past BVB for the first time since 2016.
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Schalke's latest figures confirm the club's rapid growth over the last few years. In 2002 they reported approximately 31,000 members, before reaching the 50,000 mark in August 2005 and the 100,000 milestone six years later.
They are now in second place overall in Germany, only behind Bayern Munich, who boast around 290,000 members – the most of any club in the world.