ISDA have published a 27-page report making the case for non-cleared derivatives. It is a very good read and brings to light what types of derivatives will stay out of central clearing and why. Between the lines it connects the dots between non-cleared OTC derivatives and the intended margining requirements currently being looked into by IOSCO and BCBS. From the ISDA website:

"Non-cleared OTC derivatives create significant value to the economy, from enabling companies and governments to manage risk in their operations, to helping pension funds meet their obligations to retirees. Current regulatory proposals on margin requirements pose a threat to the continued functioning of this vital market segment. This ISDA paper explains what non-cleared OTC derivatives are, who uses them, why some – but not all – will be cleared, and the impact of the regulatory proposals."

A link to the second IOSCO/BCBS consultation paper here. (This is a must-read for all practitioners in the market. This will have a significant impact on any market participant trading OTC derivatives.)