The British business was started by entrepreneurs Christina Domecq, scion of the Domecq sherry dynasty, and Daniel Doulton, a descendant of the Royal Doulton pottery family.
Despite two successful investment rounds raising hundreds of millions of pounds, it got into trouble last year after hugely embarrassing claims that human intervention played a large part in its voicemail-to-text service.
In December, the firm was bought out by US communications giant Nuance Communications, but it has emerged that investors will collect just £600 from the $102.5m sale.
In the letter to shareholders, quoted in the Telegraph newspaper, Spinvox said: "A total of around £600 was paid for all the shares, with holders of A shares being paid in priority to ordinary shareholders. Ordinary shareholders received no payment for the transfer of their shares."
Shareholders receiving nothing include Goldman Sachs and Charles Dunstone’s Carphone Warehouse as well as the founders and staff.
The money raised from the sale was in the main used to pay off emergency loans given to Spinvox when it was threatened by bankruptcy last summer.