On January 1st, 2019, a license-based system allowing online commercial companies to operate and advertise in the Swedish market was introduced. According to the Gambling Act, advertising should be ‘moderate’. Legislative changes are windows of opportunities where stakeholder interpretation and adaption may result in new agenda-setting based on conflicting interests. This article examines how stakeholder groups initially perceived and interpreted this key concept of moderation. Data from semi-structured interviews, seminars and press conferences, as well as policy documents and statements, were analyzed using a framework method approach. Contrary to what is stated in the legislation, stakeholders defined ‘moderation’ in terms of both content and volume. Although industry and media representatives requested further guidance for interpreting ‘moderation’, they favored self-regulation and allowing market consolidation. There was a notable ambivalence within and between stakeholder groups concerning balancing freedom of expression, market protection, consumer protection and public health. In conclusion, legislation is a blunt steering instrument when key concepts are largely left to stakeholders, with opposing interests, to interpret. Our study shows the incremental and interactive character of policy-making, where new legislation resulted in new policy responses. Case law and market consolidation take time and regulatory interventions need to take this into account.