> "Type in a search query for a cleaner to come to your house; rather than send you to third-party sites, Google would bake the options directly into the top o

> "Type in a search query for a cleaner to come to your house; rather than send you to third-party sites, Google would bake the options directly into the top of results." I remember hearing that Google can't aggressively promote their own services in search results. (Example: When I google "search", the top 4 hits are Yahoo, search.com, AOL, & DuckDuckGo.) Is this a proactive measure on their part to keep anti-trust regulation at bay, or an established prohibited practice? In the latter case, is there any guidance around where 'the line' is regarding this behavior?