to join the Bluetooth Special Interest Group both CSR and Broadcom must have signed to give all other members the right to implement the Bluetooth standard and to infringe any patents required to exercise that right - but perhaps that is beside the point
I guess CSR must be having enough patents to attack Broadcom in Bluetooth and other wireless domain. So most likely the CSR-Broadcom fight will end up in some sort of cross licensing deal. Considering this, It was a good strategic move by CSR to grab litigation burdened SiRF at a low price of ~130 m$
Applying patents to communications interfaces is a form of market domination. All who use the interface to communicate must pay for the rights. This restraint on communications seems most undesirable. Yet not allowing a chance to gain value with patents, does not address the need for motivation to create a better interface. There is a balanced solution.
Adaptable interfaces are needed in all public programmable communications interfaces. Such interfaces allow the means to negotiate which features (and related IPR) are used.