This is an interesting area of law. Eric Goldman has an rundown of the issues.

In my mind, there’s no question that a blogger grants an implied license to the content in an RSS feed. However, because it’s implied, I’m just not sure of the license terms. So, in theory, it could be an implied license to permit aggregators to do whatever they want.
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It is trivial to destroy an implied license, so bloggers can overcome any aggregator use simply by saying so. I’m not sure WHERE the blogger would need to say this (by the “syndicate” link? in the xml feed itself?). Perhaps any disclosure in any reasonable place would be sufficient to destroy the implied license.

So it would seem that Tobias has reasonably withdrawn his implicit license by placing the notice in the feed itself, as a post. The question of where a reasonable place to put such a notice is important. Since one can subscribe to an RSS feed without ever visiting the parent site, I think perhaps the only reasonable place for a terms of service for a feed is within the feed itself. Snow vs. DirectTV suggests that a warning isn’t necessarily enough to overcome an implicit license. Of course, I am not a lawyer so my interpretation may be flawed.

So what did PHP freaks do to incur Tobias’ ire? They republish content from RSS feeds and added advertising. I think adding advertising to aggregated content is perfectly legal. (I’m sure Google and Yahoo see things the same way when they place advertising in their web based mail readers.) However, phpfreaks uses an contextual advertising that replaces words in the content with advertising links, shades of the microsoft smart tags debacle. In PHP freaks’ favor they are very clear about attributing the source of their syndicated content and the fact that it is syndicated. Many aren’t. Additionally, the links are marked with a double underline and cause a hover box to appear which clearly labels them as advertising.

Still, I suppose one could make the argument that it is unclear who placed the advertising in the content, php freaks, or Tobias. For that reason, I think this form of advertising on third party content cross a line.

I am not anti-advertising in general. Advertising directly and indirectly pays many of my bills and I don’t begrudge someone else the opportunity to make a buck. I am also a publisher of copy righted content. And I’d rather that I made the buck off of my content than someone else. I think Tobias has the right to control the use of his material.

What do you think?