If the directive of Goldman Sachs wants to hack your website, the break attemps will come from the NSA offices (and probably you won't notice them in your logs after they got in). But individual persons (that could have an IP in that range, or get an unsecured access point) and individual computers (parts of botnets, running trojans, something that works as a proxy, etc) are everywhere.
C: It's obviously just a piece of malware on one or two of their computers doing automated scans.