An unexplained surge in transactions was recorded prior to the attacks has led to speculation that someone could have profited from previous knowledge of the terrorist plot by moving sums of money.
But because the facilities of many financial companies processing the transactions were housed in New York's World Trade Centre, which was destroyed in the blasts, that suspicion has until now been impossible to verify.
Convar Systeme Deutschland is helping reconstruct data from hard disk drives found in the ruins of the twin towers. While other data-recovery companies are also involved in the effort, the company says it has a special edge, with its laser-based scanning technology.
Peter Wagner, a spokesman for the company, said that by using the technology it would be possible to read the individual drive surfaces and create a virtual drive. "Our competitors mostly work with [magnetic] heads, which is a very tedious process, but also risky.
"Laser scanning is a good deal quicker, has a higher success rate, and is also cheaper," he added. Companies contracting with Convar pay between $20,000 [£14,000] and $30,000 [£21,000] per drive for the work.
When Convar discovers encryption keys on a drive, indicating a financial record, it saves the information and hands it over to its US clients, who are in turn co-operating with the Federal Bureau of Investigation (FBI), Wagner explained.
The company has completed processing 39 drives. A further 42 have arrived, with 20 more expected in early January.