The Wikimedia Foundation (in English: Wikimedia Foundation, Inc.) is a non-profit organization, in accordance with the legal typology of article 501 of the United States Federal Code. It is instituted under the 501c laws of Florida, United States. Its existence was officially announced by the CEO of Bomis and co-founder, along with Larry Sanger, of Wikipedia, Jimmy Wales on June 20, 2003. It is based in San Francisco, California, United States. The acting president of its Board of Directors is Nataliia Tymkiv after María Sefidari resigned from her position. Katherine Maher was the CEO since June 2016; she however she resigned in April 2021.  
It is the parent organization of Wikipedia, its most successful project and one of the ten most visited websites in the world, as well as Wikinews, Wiktionary, Wikibooks, Wikiquote, Wikisource, Wikimedia Commons, Wikispecies, Wikiversity, Wikidata, Wikiviajes in its various languages .
In 2021, it employs more than 550 employees and contractors,  with annual revenues exceeding $ 150 million. 
The Wikimedia Foundation was created from Wikipedia and Nupedia on June 20, 2003,  the application for registration was filed with Wikipedia's United States Patent and Trademark Office on September 17, 2004, the registration was Granted January 10, 2006.
Trademark protection was granted by Japan on December 16, 2004, and in the European Union on January 20, 2005. Technically, the scope of the trademark is for: 'Provision of information on general encyclopedic knowledge through Internet". There are plans to license the use of the Wikipedia trademark for some products such as books or DVDs. 
The name "Wikimedia" was coined by Sheldon Rampton on a mailing list (WikiEN-l) in March 2003. The domain names Wikimedia.org and Wikimediafoundation.org were acquired for the Foundation by Daniel Mayer.
With the announcement of the foundation, Wales transferred ownership of the domain names of Wikipedia, Wiktionary, and the free encyclopedia Nupedia, along with the rights to all materials related to these projects that were created by Bomis employees or by Wales himself. . The computer equipment used to run all Wikipedia projects was also donated to the foundation by Wales, who also acquired the domain names "wikimedia.org" and "wikimediafoundation.org".
In April 2005, the US Tax Service approved (by letter) the foundation as an educational foundation.
On December 11, 2006, the Wikimedia Foundation Board noted that the corporation was unable to become a membership organization as initially envisioned, but was never implemented due to the inability to meet the registration requirements of the Bylaws of the Wikimedia Foundation. State of Florida, USA Accordingly, the bylaws were amended to remove all reference to member rights and activities. The decision to change the statutes was approved by the Council unanimously. 
On September 25, 2007, the Wikimedia Foundation Board announced the relocation of the Foundation's headquarters to San Francisco Bay, due to the proximity of other like-minded organizations and potential partners, as well as the convenience for carry out international travel.   
On April 16, 2010, the 109th edition (one billion or "one billion") was reached for one of the Wikimedia projects. 
In October 2011, the Wikimedia Foundation announced the launch of Wikipedia Zero, an initiative to enable free mobile (data) access to Wikipedia in third world countries through collaborations with mobile telecommunications operators.