Nov 12 (Reuters) - Theranos founder Elizabeth Holmes should spend 15 years in prison and pay $800 million in restitution to investors defrauded in the blood testing start-up, U.S. prosecutors recommended late on Friday. The Department of Justice recommendation, made in a court filing, came as Holmes prepares to be sentenced next week. "Considering the extensiveness of Holmes' fraud... the sentencing of 180 months' imprisonment would reflect the seriousness of the offenses, provide for just punishment for the offenses, and deter Holmes and others," the prosecutors said. Holmes earlier urged U.S. District Judge Edward Davila in San Jose, California not to send her to prison. Holmes founded Theranos in 2003 at the age of 19.

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