How do you ensure valid W3C XHTML when using affiliate links?

It seems that most affiliate programs (e.g. Amazon, Linkshare, etc.) provide non W3C compliant XHTML code fragments. When I use the W3C valida开发者_Python百科tor I get hundreds of errors and warnings on any pages that use affiliate links.

Mostly the issues are non-encoded special characters, but there are other problems too.

I'm a bit worried about the impact on SEO, but it also just clutters the validator output and makes it extremely hard to use.

If you use affiliate links, how do you deal with this? Hand-correct the markup?

Does it matter?

Lengthy w3c error reports have no effect on SEO or SERPs if the errors are merely improperly escaped entities within affiliate URLs. I stopped using w3c to validate my pages because the error reports are just ridiculously long, perhaps they need to adjust the tool to ignore affiliate codes. Chrome and IE have debugging tools that are decent and free, just check under the options or tools menu.