Guaranteed Returns, a Holbrook-based firm that returns expired and unsellable drugs to manufacturers, plans to lay off 109 people and wind down operations by May 24 according to a notice filed with the state Department of Labor Friday.Guaranteed Returns receives medications from wholesale or retail sellers and health care facilities and sends them back to manufacturers with the goal of helping facilities and pharmacies, including those operated by the federal government, manage their inventory. Some of its customers include Black Rock Pharmacy, based in Buffalo, and Boca Pharmacy Group which has several locations in the Bronx.The 109 workers represent the company's entire workforce, according to the notice. Guaranteed Returns plans to lay off 22 employees on March 15, 53 staff members on April 12, 17 workers on April 26 and the remaining 15 employees on May 10 and 24, citing "economic" reasons. The layoffs come weeks after Guaranteed Returns posted a letter from president and chief executive Paul Nick on its website informing customers that the company had been placed on the U.S. Department of Health and Human Services' exclusions list. The exclusions program prohibits firms from receiving payment from federal health care programs, including because of Medicare and Medicaid fraud.The listing is a result of legal action against Guaranteed Returns, Nick wrote in his letter, that concern activity at the company between 1999 and 2014. About five years ago, brother and sister duo Dean Volkes and Donna Fallon, the firm's owner and chief financial officer, were sentenced to years in prison after being convicted of conspiring to steal money from their clients, obstruction of justice and theft of government property. According to the U.S. Attorney's Office, between 1999 and 2014 Volkes and Fallon stole more than $100 million from more than 13,000 customers, including more than $20 million from medical treatment facilities operated by the U.S. Department of Defense and other agencies. As part of their sentencing, Guaranteed Returns and Volkes were each ordered to forfeit $115 million, Volkes was ordered to pay $95 million in restitution and the attorney's office ordered Fallon to pay $515,000.Reports show that in January of 2023 Volkes and Fallon won their appeal of the convictions when the court ruled that evidence did not show that the company's financial transfers were designed to conceal fraud. The case was sent back to trial for their sentences to be recalculated, although the judge upheld all of their other convictions.As of Feb. 20 this year, Nick wrote to customers, Guaranteed Returns is no longer accepting any medications for return and the firm is working with wholesalers to determine how to handle outstanding credits.Representatives from Guaranteed Returns did not respond to requests for comment about the layoffs. The company was founded in 1986.