(In headline, adds dropped closing quote mark.)

By Luc Cohen

NEW YORK, March 20 (Reuters) -

Sam Bankman-Fried is no "super-villain" and should not spend

a "medieval" 40 to 50 years in prison as prosecutors propose,

lawyers for the founder of bankrupt cryptocurrency exchange FTX

said in advance of his sentencing next week.

In a court filing late on Tuesday, the 32-year-old former

billionaire's lawyers said a sentence significantly lower than

the 5-1/4 to 6-1/2 year guideline range they had previously

proposed would be appropriate punishment for his November

conviction on charges of stealing $8 billion from FTX customers.

"The memorandum distorts reality to support its precious

'loss' narrative and casts Sam as a depraved super-villain,"

defense lawyer Mark Mukasey wrote.

"It adopts a medieval view of punishment to reach what

amounts to a death-in-prison sentencing recommendation."

Mukasey had previously said FTX customers were likely to be

made whole as a result of the bankruptcy process, and that

Bankman-Fried worked diligently after FTX's November 2022

collapse to recover funds before he was arrested the next month.

Bankman-Fried pleaded not guilty to seven counts of fraud

and conspiracy and has vowed to appeal his conviction and

sentence. In testifying at his month-long trial last year,

Bankman-Fried acknowledged making mistakes while running FTX but

said he never intended to steal funds.

Prosecutors disputed that in their sentencing memorandum

last week, arguing Bankman-Fried gambled with his customers'

money out of greed and has refused to admit that what he did was

wrong.

In court filings this week, several FTX customers said they

would be dissatisfied with being compensated based on the dollar

value of their holdings at the time the exchange declared

bankruptcy because their cryptocurrency assets would be worth

much more today.

U.S. District Judge Lewis Kaplan is due to sentence

Bankman-Fried at a March 28 hearing in Manhattan federal court.