I think this is way too far. For me personally, the threshold to put the logo is someone within the company is paying, even though the whole company is not in a contract. For example, you might not have a full fledged contract with Google, but one manager of a tiny team might have used her/his company credit card to pay for your tool. If the sum is below a certain threshold, they don't need to authorize or go through vendor vetting and all that.