It said a resentencing was warranted because a recent Supreme Court ruling raised questions as to whether a loss estimated by a lower-court judge at between $20 million and $50 million should include investments purchased overseas. A lower calculation could result in a lower sentence.
Convicted in 2008, Vilar was sentenced to nine years and Tanaka to five years in prison.
The court said Vilar and Tanaka promised investors their money would be invested in high-quality, short-term deposits including U.S. Treasury bills but then put their money in technology and biotechnology stocks that collapsed in value when the dot-com bubble burst in fall 2000.
At trial, witnesses against Vilar included Lily Cates, the mother of "Fast Times at Ridgemont High" actress Phoebe Cates, who said he improperly spent $5 million of her money.
The court discounted arguments that Vilar and Tanaka should be shielded from criminal blame because investments were carefully structured to occur overseas.
"In other words, Vilar and Tanaka argue that their very intention to evade U.S. law is evidence of their innocence. We see no reason to rescue fraudsters when they complain that their perfect scheme to avoid getting caught has failed," it wrote.