If you are adding a logo be sure to link to the site as well. This adds a SEO + traffic benefit and makes a request for removal less likely. We put logos of i

If you are adding a logo be sure to link to the site as well. This adds a SEO + traffic benefit and makes a request for removal less likely. We put logos of integration partners and they are generally quite pleased. Our homepage is a PR5 backlink which is pretty valuable. I would not recommend using customer logos without asking first. However, I would assume that most would be happy to get the SEO juice and any traffic that comes along with the link.