Events in more than 60 countries were designed to promote open documents and standards. Teams were equipped with flags, T-shirts and stickers to raise awareness of the ODF.
"We are very happy about the response and activities that teams around the world have scheduled," said Ivan Jelic, coordinator of the programme.
"Activities range from local speeches and information events to prizes for governmental bodies that adopted good policies in the field of document freedom and open standards."
Google, which has long been a backer of the ODF standard and an advocate of open formats, was among the companies supporting the event.
"When you save a document, you need to be sure that the information in it will be accessible tomorrow, a month from now, 10 years from now," wrote Google open source programmes manager Zaheda Bhorat in a blog posting.
"How and where you choose to access your documents should not make a difference. This is what Document Freedom Day is about."
The event is the latest chapter in the bitter fight over open document standards. ODF and its backers, which include IBM and Sun Microsystems, have been engaged in a bitter feud with Microsoft and its OpenXML format.
The two camps are fighting over control of a new class of open documents and the clients that come with it.
Government organisations around the world have begun mandating that employees switch to an open format that can be shared across various agencies and localities.
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