The first application was made by Mutya Buena in November, however it was yesterday resubmitted to include Keisha Buchanan and Siobhan Donaghy.
Website Holymoly has obtained papers showing the application by managers acting on behalf the three singers.
Donaghy was first to quit the band in 2001, followed by Buena in 2005. Buchanan became the final founding member to leave the group in September 2009.
The current lineup, which includes Heidi Range, Amelle Berrabah and Jade Ewen, reportedly only have until May 8 to launch an official opposition.
Range yesterday denied that there was a dispute over the name, insisting that Universal Records have ownership of the brand.