By Tony Hanson

PHILADELPHIA (CBS) — Federal authorities say the Nifty Fifty’s restaurant empire was built on greed, and the secret ingredient was crime.

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Company owners and managers have pleaded guilty to a massive, decades-long tax fraud scheme, and this week they were being sentenced.

Sentences have ranged from a year and a day to three years. The final sentencings took place today.

Prosecutors say the defendants skimmed over $15 million from sales and avoided over $2 million in taxes.  Prosecutor Paul Shapiro says they’ve since paid that back, and more.

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“Including penalties and interest collected by the government to date, it exceeds four million dollars,” he said today.

Authorities say there was more than greed: cheating on taxes was a simple “founding principle” of the business.

“The money was used to grow the business, which allowed them to compound the criminal proceeds of their scheme, because with each new location there were more sales and greater opportunity to avoid taxes,” says prosecutor Nancy Potts.

Defendants have been ordered to report to prison just after the new year.

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