The court yesterday rejected a plea to free them from detention during a trial being seen as a test for press freedom under President Recep Tayyip Erdogan.
The case, which opened in Istanbul in July, involves 17 current and former writers, cartoonists and executives from Cumhuriyet, including editor-in-chief Murat Sabuncu and chief executive Akin Atalay.
The court justified its decision to keep the staff members in custody by saying it had been unable to question three witnesses called to the stand yesterday.
Applause erupted in the audience as the men were escorted from the courtroom.
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For government critics, the case is emblematic of the erosion of freedom following last year's failed coup, when Ankara launched a crackdown targeting those with alleged links to the putschists as well as opponents.
The secular daily is one of the few voices in the Turkish media to oppose Erdogan, with its embarrassing scoops angering those in the corridors of power.
On July 28, an Istanbul court freed seven of the newspaper's staff after 271 days, including respected cartoonist Musa Kart and Turhan Gunay, editor of the books supplement.
Gursel was defiant when he took the stand, claiming he was on trial because of his "journalistic activities".
"Whatever the verdict, I have an untroubled conscience. And if there is even a little bit of justice left in this period where justice has been trampled upon, I know I will be acquitted," he said.
Gursel, Sabuncu and Atalay have been jailed for 316 days, while Sik has been held for 255 days. If convicted, they face varying terms of up to 43 years.
Once a close ally of President Erdogan, Gulen is in self-imposed exile in the United States, wanted on charges of ordering the failed July 2016 coup, allegations he denies. More than 50,000 people have been arrested on suspicion of links to his movement.
Those on trial are charged with using their position to support the Gulen movement, along with the Kurdistan Workers' Party (PKK) and the ultra-left Revolutionary People's Liberation Party-Front (DHKP-C).
In the indictment, the newspaper was accused of an "intense perception operation" targeting both Turkey and Erdogan using the tactics of an "asymmetric war".
The judge asked several witnesses, including Cumhuriyet journalists and former members of the foundation which owns the daily, about its financial situation and the editorial process, including how headlines are chosen and the angle of stories.
Editor-in-chief Sabuncu condemned the trial, telling the judge it "has unfortunately already entered the darkest pages of the history of press freedom" in Turkey.
Christophe Deloire, Reporters Without Borders (RSF) secretary general, said the journalists "are judged simply because they embody the journalism worthy of its name in Turkey and they do not broadcast the propaganda of the Erdogan regime".
According to the P24 press freedom group, there are 170 journalists behind bars in Turkey, most of whom were arrested after the coup.
The country ranks 155 out of 180 on the latest RSF world press freedom index.