I was visiting www.buy.com when Bugnosis told me about a Web bug from ad.doubleclick.net. Which company is responsible for the Web bug: Buy.com or Doubleclick.net?
The companies may have decided together to place the Web bug on Buy.com s page. In fact, both Web sites need to add a little bit to their Web servers to put the Web bugs there. However, sometimes the main site the one you are aware of visiting defers such matters to the site actually providing the bug.