Regulatory regimes designed to ensure transparency often struggle to ensure that transparency is meaningful in practice. This challenge is particularly great when coupled with the widespread usage of dark patterns - design techniques used to manipulate users. The following article analyses the implementation of the transparency provisions of the German Network Enforcement Act (NetzDG) by Facebook and Twitter, as well as the consequences of these implementations for the effective regulation of online platforms. This question of effective regulation is particularly salient, due to an enforcement action in 2019 by Germany's Federal Office of Justice (BfJ) against Facebook for what the BfJ claim were insufficient compliance with transparency requirements, under NetzDG. This article provides an overview of the transparency requirements of NetzDG and contrasts these with the transparency requirements of other relevant regulations. It will then discuss how transparency concerns not only providing data, but also how the visibility of the data that is made transparent is managed, by deciding how the data is provided and is framed. We will then provide an empirical analysis of the design choices made by Facebook and Twitter, to assess the ways in which their implementations differ. The consequences of these two divergent implementations on interface design and user behaviour are then discussed, through a comparison of the transparency reports and reporting mechanisms used by Facebook and Twitter. As a next step, we will discuss the BfJ's consideration of the design of Facebook's content reporting mechanisms, and what this reveals about their respective interpretations of NetzDG's scope. Finally, in recognising that this situation is one in which a regulator is considering design as part of their action - we develop a wider argument on the potential for regulatory enforcement around dark patterns, and design practices more generally, for which this case is an early, indicative example.