In a posting to the foundation's technical blog, the group said that it would be asking to be excluded from the advertising programme, which tracks user behaviour for use in targeted advertising.
"After some internal discussion on whether opting out of the Phorm user-profiling system in the UK would legitimize it, we’re going ahead and requesting an opt-out for all the domains under the Wikimedia Foundation's control," read the posting.
Among the sites which will covered by the request are Wikipedia, Wikidata, Quickipedia and Wikidisclosure.
The move makes Wikimedia the latest company to ask that it be excluded from Phorm. Last week, Amazon said that it would also ask for its domains to be taken out of the programme.
Since word first surfaced that BT was looking at launching a new advertising based on Phorm, the company has been under attack from privacy advocates who said that the tracking behaviour goes too far and violates the rights of customers.
More recently, the EU has jumped into the fray, not only condemning Phorm but also filing suit against the UK government for allowing telcos to use the system allegedly in violation of EU privacy rules.