Prism and Facebook agree on public data collection transparency after 10K requests in six months

Company can communicate figures "only in aggregate and as a range", says Facebook lawyer

After revealing that it received as many as 10,000 data requests in the latter half of 2012 – amounting to between 18,000 and 19,000 user accounts – Facebook has also publicly revealed more about the relationship between it and the US government's so-called "Prism" project, which has been allegedly secretly collecting data from internet firms in recent months.

The firms accused of offering up information to the NSA – which include Google, Yahoo, Apple and Microsoft, as well as Facebook – still categorically deny giving direct data access to the government, but have admitted to complying with requests backed by law.

In a blog post written on Friday and entitled "Facebook release data, including all National Security Requests", the company's lawyer Ted Ullyot stated that "as of today, the government will only authorise us to communicate about these numbers in aggregate, and as a range", before reeling off the statistic of "between 9,000 and 10,000" security-related data access requests coming from the government in the six months ending 31 December 2012.

Ullyot revealed that requests resulted from a "gamut" of inquiries, ranging from missing child cases to tracking fugitives or terrorists – the emphasis being on specific case-by-case access requirements rather than the alleged wholesale information tracking, which was central to reports surrounding US telco Verizon, and began the Prism saga two weeks ago.

Ullyot said Facebook will "continue to be vigilant in protecting our users' data from unwarranted government requests, and we will continue to push all governments to be as transparent as possible".