The musician sealed his commitment to veganism with the new ink.
The singer has been embroiled in a controversy with the actress after making claims that they dated in his new memoir, "Then It Fell Apart."
The musician said he "should've acted more responsibly and respectfully" toward the actress when they first met.
Moby insists he and Natalie Portman dated in the late '90s, which Portman has openly denied. The "Why Can't I?" singer tweeted what might have happened between them.
"What do you do when people believe lies and accusations and not actual photographs and evidence?” the 53-year-old musician wrote.
The musician claimed the two dated when Portman was in college and he was 33 years old. She vehemently disagrees.
Moby spoke with HuffPost about activism and becoming a reluctant mouthpiece for anti-Trump intel.