In 2005, PFOS was proposed for listing under the Stockholm Convention. Four years later, in May 2009, it was added to Annex B of the Stockholm Convention. The amendment entered into force on 26 August 2010 for all Parties that had not submitted a notification pursuant to the provisions of paragraph 3(b) of Article 22. PFOS has been used for many applications due to its outstanding surface properties as a water repellent. This physical property is especially used to increase water and stain repellence of leather, paper or textiles such as carpets.