But unlike other more common thieves brazenly living beyond their means, his contraband wasn't jewelry or electronics -- it was toner for copiers and printers.
The $1.5 million scheme at the prestigious Memorial Sloan-Kettering Cancer Center exploited what New York City authorities describe as a largely overlooked, yet lucrative black market for toner cartridges and other office supplies.
Businesses have long endured employees pilfering pens, paper clips and other items for personal use, called "supply-jacking." But schemes like Gumbs' go much further, with the perpetrators using business accounts to place false orders for more costly items such as toner, then reselling them at a steep discount.
Fried, Frank, Harris, Shriver & Jacobson, a large law firm in Manhattan's financial district, recently became the scene of another toner caper that ended with grand larceny charges against Adrian Rodriguez, who worked in the duplicating department.
"This defendant didn't just take a box of Post-it Notes out of the office supply closet," District Attorney Cyrus Vance Jr. said in announcing the case.
Prosecutors allege the 38-year-old Rodriguez, who pleaded not guilty this month, ordered more than $376,000 in excess toner from two vendors over a two-year period. He would sell the cartridges -- worth $80 to $259 a piece -- for as little as $10 "out of the firm's back door ... and using the money to party and otherwise finance his lifestyle," according to court papers.
During a sting operation in late December, undercover investigators went to the law firm and delivered a shipment of cartridges that was marked so it could be tracked. They then watched as Rodriguez stashed the cartridges away before directing an unidentified buyer driving a van to pick them up at a loading dock, the court papers say.
Who buys the stolen toner and the scope of the thievery in the city, and what the victims have done to keep from happening again, is unclear. Authorities declined to discuss an ongoing investigation of the black market and where it's leading, and there was no response to messages left with the Fried Frank law firm and Memorial Sloan-Kettering.
Alicia Ellis, a spokeswoman for the National Office Products Alliance, said the Washington, D.C., trade group has heard many stories about office products dealers getting ripped off by bogus clients using stolen credit cards to order products -- primarily toner, but not about employees of legitimate purchasers enriching themselves with inside toner jobs.
Still, there have been isolated cases.
In 2007, two Pennsylvania men were accused of stealing $187,000 worth of ink and toner from their office-supply employer and then selling the goods on the Internet. The same year, an account executive at a New Jersey stationery supply company pleaded guilty to stealing 30,000 toner cartridges valued at $1.75 million.
The con game at Memorial Sloan-Kettering dates to 2007, when one of Gumbs' duties as a receiving clerk paid $37,800 a year was to order supplies from an Office Depot website. Prosecutors accused him of ordering $1.5 million in cartridges -- priced at $200 a piece -- that didn't fit any of the copiers and printers at the hospital.
Gumbs also short-circuited hospital procedures by having delivery drivers call his cellphone and meet him at the curb outside. He then stashed the toner in a garbage area so he could retrieve it later.
By the time he was done, Gumbs had used his fraudulent profits to rent a luxury apartment in suburban Westchester County, make a $50,500 down payment on a BMW, and pay for shopping sprees at Burberry, Fendi and Gucci stores. Bank and credit card records showed deposits of $150,000, and purchases of airline tickets and hotel rooms in Las Vegas; Cancun, Mexico; and Orlando, Fla.
Gumbs, 34, pleaded guilty last year and was sentenced to 2 1/2 to 7 1/2 years behind bars. He also was ordered to forfeit his BMW, Rolex, laptop computers, four Louis Vuitton bags and other items bought with ill-gotten gains.