2.29 The assumptions made about costs created a level of uncertainty in the public sector comparator. During the development of the comparator PITO was aware that O2 was engaged in price negotiations with Nokia and Motorola, two members of the O2-led consortium. Not wanting to undermine O2's bargaining position by giving any impression to these manufacturers that there was an alternative to Airwave, PITO instructed Mason Communications not to approach the market for cost information, but to use only its own cost information to price the comparator. Furthermore, to preserve the independence of the comparator, those employees of Mason Communications involved in analysing costs input into the should-cost model were not consulted. While Mason Communications had a wealth of cost information about radio communications, it possessed only publicly available costs of TETRA equipment.