The cat had a significant Internet following of its own - though its views hewed suspiciously close to its human's - and it was apparently a fixture at the embassy, with a penchant for pouncing on Christmas tree ornaments and for defusing tension as Assange tangled with a bevy of world leaders.
It was named for its famous home, but occasionally went by "James" or "Cat-stro" after the Cuban leader Fidel Castro's death in 2016.
Its Twitter and Instagram accounts - with 31,000 and 5,000 followers, respectively - also monopolised the coveted market for cybersecurity-meets-cat puns (the cat was reportedly interested in "counter-purrveillance").
So when British police stormed the Ecuadoran Embassy, arrested Assange and
took him into custody after a United States federal court unsealed an indictment charging him with conspiracy, many worried about the fate of the feline.
Italy's La Repubblica newspaper reported in November 2018 that the cat was gone. But, according to the paper, its departure was for its own good, a benevolent gesture by its owner.
The author, who visited Assange for the story, wrote: "Not even the cat is there anymore... Assange has preferred to spare the cat an isolation which has become unbearable and allow it a healthier life."
Sputnik News, the Russian government-funded Kremlin organ and diligent reporter of Embassy Cat developments, said it had contacted the Ecuadoran Embassy about the cat and a spokesman confirmed that it had been gone for months.
"It is not here since September, I think," the official told Sputnik. "It was taken by Mr Assange's associates a long ago... It is not here. We are not a pet store, so we do not keep pets here."
Mr James Ball, an early employee of WikiLeaks who defected after three months at the organisation, said on Twitter that the embassy gave the cat to a shelter "ages ago". He also wrote that he "genuinely offered to adopt it", though it doesn't appear that Assange took him up on it.
But the person closest to Assange to comment on Embassy Cat, a member of his legal team, said Assange gave the cat to a family member after the Ecuadoran Embassy threatened to take the pet to a shelter.