Ann Nimiriano, co-editor of the Juba Monitor newspaper, told The Associated Press that the elderly Taban remains in hospital where he was transferred while in detention.
Amnesty International said Taban had been charged with "publishing or communicating false statements prejudicial to Southern Sudan" and "undermining the authority of or insulting the president."
Taban's article called for South Sudan President Salva Kiir and First Vice President Riek Machar to step down after fighting in the capital Juba between their forces killed hundreds.