The Competition Commission (CC) has blocked BOC Limited's proposed acquisition of Ineos Chlor Limited’s packaged chlorine business. The packaged chlorine market is a niche market that is relatively low in value. In cases where the total value of the relevant market is below £10m, the Office of Fair Trading (OFT) has the discretion to treat a merger affecting that market as de minimis i.e. of relatively minor importance. Nevertheless, in this instance the OFT was concerned that the merged entity would hold approximately 80% of the packaged chlorine market. It therefore referred the transaction to the CC for an in-depth investigation. Following that investigation, the CC found that the merger is likely to result in higher prices for packaged chlorine in the UK and would eliminate an important player from the market. Consequently, the CC concluded that the only suitable remedy is to block the merger.