How do you filter out ISPs from inferred company on anonymous lists?

Diederik,  great suggestion!  I have a little over 80 ISPs (mostly Noth American) in my list that I use mostly for form validation to ensure that we get business email addresses.  It would be great if you could share your list.  Can you provide a link?  If not, I would really appreciate if you could email it to me (elowe@conductor.com).  Include your email address and I'll share my list as well.

I have a custom list with over 3000 ISP's in a smartlist in Marketo. The smart campaign sets my custom field Is_ISP to true. If I find new ISP's I will add them to my list. I added this custom field to web activity reports in addition to the Marketo ISP setting (which only looks at the US). Too bad you can't use it for Insights in Salesforce.

Without an email address or a name its hard for a data vendor to append to anonymous leads.  We use Data.com for our known Leads/Contacts/Accounts, and are looking at implementing Reachforce as well.

Thanks, Elliott. I've just manually built a list of ISPs best I can to exclude. 

I was curious if you have any preferred vendor for appending data to these anonymous lists?

I'm trying Jigsaw, but quality isn't great.