As with all Customer Commons terms, #P2B1(beta), aka #NoStalking can be read by lawyers, ordinary people, and machines:
P2C means person to company, and the 1 means this is the first term of this kind.
In summary form, P2B1 means “don’t track me off your site, and don’t let others track me on your site or anywhere else.”
Or, to sites that run advertising, it means this:
In machine-readable form, P2B1 is still in development. But If a browser points to this page, the person’s intent is still clear.