My experience also is that there is pretty limited sharing, even among business partners. The worst was when the idiots at Aweber, the email marketing service,

My experience also is that there is pretty limited sharing, even among business partners. The worst was when the idiots at Aweber, the email marketing service, were hacked, and I had waves of spam coming in on many per domain emails. Six months later, Aweber was hacked again. Another wave.