In the latest revelation about Facebook's data-sharing practices, the social media giant acknowledged Friday that it gave certain companies extended, special access to user data in 2015 -- data that was already off limits to most developers.

As the Wall Street Journal first reported, certain companies were, for a time, granted access to data about users, as well as data about those users' friends. These arrangements existed even though Facebook had already changed its third-party data access policy, making it more restrictive.

The companies that received this special access to data included Royal Bank of Canada and Nissan Motor Co., Facebook confirmed to ZDNet.

A Facebook representative told ZDNet these agreements were "extremely short-lived" and that they have all ended. Furthermore, the spokesperson said the data was not shared in exchange for anything of value, monetary or otherwise.

There are two scenarios in which Facebook works more closely with developers and partners, the spokesperson said: First, when the company is depecrating APIs, some developers need more time to work through the changes -- Facebook gave RBC extended access to user data for this reason.

Second, Facebook provides special access to certain partners when testing out new features. As the Wall Street Journal reported, one such feature being tested was a "friend link" metric that measured the degree of closeness between a user and others in his network. The Facebook spokesperson told ZDNet this feature was never rolled out.

Facebook says its data-sharing agreements with RBC, Nissan and others were in line with the 2012 Federal Trade Commission settlement requiring the company to give users clear notice and obtain their consent before sharing information beyond their privacy settings.

Facebook's acknowledgement of these agreements is the latest incident to shed light on the way the company has shared user data in ways users are unlikely to understand. This week alone, the company came under scrutiny for multiple other reports of previously-unreported data sharing. On Thursday, Facebook acknowledged that it accentally exposed the private posts of 14 million users over the span of a few days last month. Earlier in the week, the company acknowledged data-sharing deals with several device makers.

Facebook has been under scrutiny, from users and government officials around the globe, since March, when it acknowledged that information from tens of millions of users had been improperly shared with the shady analytics firm Cambridge Analytica.