Blech!

I hate to ask this, but can't bite my lip, given the fact that people are throwing lawyers at this stuff now. Is it within the realm of possibility that ISP's will start to craft SLA's, peering & transit agreements, to include who is responsible for ingress filtering? I would think so. Also, if so, do you think that this would technically be effcient, given that the filters would actually be applied? Feel free to be silent, - paul