The party that conducts the technical operation of an Internet site and is responsible for the site-internal search engine maintained there uses trade marks as keywords in the context of its own commercial communication if it has the search results displayed in a list of hits chosen on the basis of an automatic analysis of customer behaviour, and the suppliers of the goods shown in the results lists cannot influence the content of the hit list.If, when viewing a list of search results generated by a site-internal search engine after entering a search term that is identical with a trade mark, a reasonably well-informed and reasonably observant Internet user cannot or not easily tell whether goods or services advertised there derive from the proprietor of the mark or a commercially related company, or rather from a third party, then the origin-indicating function of the trade mark is compromised.