The Dutch market regulator, AFM, accidentally published a list of short equity positions on its website on Tuesday.
Since the 2012 EU Regulation on Short Selling, all short positions of over 0.2% of issued share capital are required to be disclosed to national regulators. However, only those above 0.5% are made public.
The leak meant that positions between 0.2% and 0.5%, which are considered "private" and are only for the eyes of the regulators, were instead made public. The list contains data from 2013, although it is not clear whether this is the full data or a subset of it.
While this is an isolated incident and the absence of context, such as offsetting long positions, limits the amount that can be deduced from the data, it is a clear sign of the security risk that comes with the stricter disclosure requirements introduced in recent years.