Following a consultation in January, the Competition and Markets Authority (CMA) is raising the threshold for markets where mergers might not warrant investigation from £10m to £15m. It is also changing the figure for markets generally considered not sufficiently important to warrant a merger reference from £3m to £5m. The CMA has a duty to refer mergers for an in-depth, phase 2 investigation if they could lead to a substantial lessening of competition. However, it may decide not to, for example, if it believes the costs involved are disproportionate to the size of the market concerned.