For years, Google's critics have complained that for all its vaunted transparency, the company has perpetually failed to disclose a key part of its business: How much of its AdSense revenue does it keep for itself, and how much does it hand over to Web sites and blogs that host Google ads? The pressure has been ratcheting up lately, as Italian officials have pursued an antitrust investigation in response to claims by a local newspaper that Google was abusing its market share to gouge its partners. Yesterday, the company finally disclosed much—though not all—of this data.

According to a blog post from yesterday afternoon, Google shares 68 percent of the ad revenue with Web publishers, while it keeps the rest. The company has a separate deal with Web sites that host a Google search bar; those search partners only get to keep 51 percent of the revenue that results from customers clicking on ads next to search results. Google representatives claim that the higher percentage Google keeps for search reflects the costs associated with developing and improving the service, but it's also entirely possible that Google can get away with a bigger cut because the overall revenue is so much higher from the extra searches.

The Wall Street Journal claims that Google's percentages are considerably more generous than Apple's (AAPL), whose iAd mobile-advertising service only offers its partners 60 percent of the revenue. But reporter Scott Morrison is missing a key point. Google didn't disclose the share of ad revenue it will share on mobile ads; Morrison's comparing apples with oranges. And that's not the only revenue split deal Google didn't disclose. The company still hides information about revenues pertaining to ads next to games and YouTube videos. In addition, it's well known that big publishers like the New York Times negotiate separate revenue-sharing deals, but that information was nowhere to be found.