The live music company has filed a letter of complaint to The Royal Parks raising "serious concerns" about the tender and bid process for the new four-year contract up to 2017.
Although San Francisco has awarded a contract, and Chicago is just about to put one out to tender, in most American cities there is not enough city centre shopping to make the business work.
The output specification is the document on which the private sector will base its tender but is also the basis for the technical specification in the final contract document.
It concerns breaking a public procurement law by getting a contract (for supplying clocks with information panels to schools in Aquitaine) without a competitive tender.