This international day of commemoration is recognised by the United Nations, and is now marked annually by anti-vivisectionists on every continent.

In 1980, People for the Ethical Treatment of Animals (PETA), led by PETA Founder, Ingrid Newkirk, organized the first World Day for Laboratory Animals protest in the U.S.[3] Today the event is marked by demonstrations and protests by groups opposed to the use of animals in research.

[4] In April 2010 protesters marched through central London calling for an end to the use of animals in research,.

On 22 April 2009 members of UCLA Pro-Test held a rally in support of biomedical research on animals,[10] and to condemn the violence and harassment directed at faculty member Prof. David Jentsch by animal activists.

[1][13][14] However, the day is not included on the official list of United Nations observances.