1. APAs and CTPs shall charge for the use of market data on the basis of the use made by individual end-users of the market data ('per user basis'). APAs and CTPs shall have arrangements in place to ensure that each individual use of market data is charged only once.
2. By way of derogation from paragraph 1, APAs and CTPs may decide not to make market data available on a per user basis where to charge on a per user basis is disproportionate to the cost of making market data available, having regard to the scale and scope of the market data.
3. APAs or CTPs shall provide grounds for the refusal to make market data available on a per user basis and shall publish those grounds on their webpage.