Following the lead set by Google and Twitter, Microsoft has published its first transparency report, tabulating the number of requests for customer data made by law enforcement around the world, the number of responses given, and what kind of information was included in those responses.

Microsoft responds to requests for data in 46 countries, those where it says it can properly verify the legitimacy of the requests. In 2012, a total of 70,665 requests were made. The country making the most demands for data was Turkey, with 11,434. The US was in second place, with 11,073. Each request could concern multiple users, with a total of 122,015 users covered by requests.

When it comes to the number of requests that returned customer data, however, the US was the clear leader. Of 1,558 requests that resulted in disclosure of some customer content, such as the subject or body of an e-mail or a photograph on SkyDrive, 1,544 were made in the US. The other 14 were split between Brazil (7), Canada (1), Ireland (5), and New Zealand (1).

Requests involving only what Microsoft calls "transactional" data were much more evenly distributed. These requests, that might yield information such as an IP address, a name, or a billing address, were far more numerous, with almost 80 percent of all requests resulting in disclosure of this kind of information.

Turkey took the top spot here, with 8,997 disclosures of transactional information, with the US, UK, France, and Germany, all receiving 7,000-odd responses.

A minority of requests didn't result in any information disclosure. In 16.8 percent of cases, no relevant data for the accounts queried was found. Again, Turkey led here, with 2,433 requests not yielding data, with the US, UK, France, and Germany following. Some requests were also rejected for not meeting legal criteria. Almost all of these—759 out of 866 total—came from the US.

Microsoft's report breaks out data surrounding Skype separately. Skype has historically had a different reporting and recording system, so Microsoft says it can't provide the same breakdown of outcomes, though in future it will change how it collects the data so that it can provide this level of detail. The Skype data also spans a different set of countries.

The UK made the most Skype requests, making 1,268 out of a total of 4,713. The US made the second most requests, 1,154. In all, law enforcement asked for information about 15,409 different Skype accounts. None of the requests resulted in disclosure of customer content, but an undisclosed number resulted in disclosure of transactional data.

Slightly more detailed information exists for the second half of 2012. In that period, Skype's compliance team found no information about 2,847 of the accounts queried. The Skype team also provided "guidance" to law enforcement, such as an explanation about why a request was rejected or information about the process for obtaining data, in 501 cases.

Going forward, Microsoft plans to update the report every six months.

The company also provided information beyond that contained in the report. Strikingly, Microsoft addressed only 11 requests that concerned enterprise customers using Office 365, Azure, or other cloud services. Of those 11, seven were rejected outright or redirected to the customers' own legal departments. The remaining four, that resulted in some information disclosure, were either done with the customers' consent, or after following the terms of the enterprise contracts.

Over 2012, Google in comparison had 42,327 requests in total, concerning 68,249 accounts. Of these, 16,407 were made in the US, and about 14,600 resulted in information being disclosed (Google provides no data about whether the information is content or transactional). As such, Google receives more requests about US data than Microsoft, and responds to a higher proportion: 89 percent for Google, 79 percent for Microsoft.

Conversely, Microsoft responded to far more requests outside the US. Of 25,920 non-US requests, Google responded to barely half: 13,478, or 52 percent. Microsoft attributes this difference in non-US reporting to its greater presence in countries around the world, which makes it easier for courts and law enforcement agencies to contact Microsoft to request data.

The lack of information about Skype may frustrate an on-going effort by privacy advocates and activists to get Microsoft to publicly state what data it can collect from Skype users, what data it does collect from Skype users, what its procedures are when asked for data, and what its relationship is with TOM Online, a Chinese company that operates licenses Skype's technology for use in China and that provides a modified Skype client that performs censorship of Skype chats. These concerns were raised in an open letter published in January. Microsoft is yet to respond to the letter.

Though today's transparency report does provide some of the information requested, it also indicates that Microsoft doesn't have all the data that the open letter's signatories would like. Future records should be more complete, however.