The common law principle of privity of contract (see http://en.wikipedia.org/wiki/Privity_of_contract http://en.wikipedia.org/wiki/Privity_of_contract) means th

The common law principle of privity of contract (see http://en.wikipedia.org/wiki/Privity_of_contract http://en.wikipedia.org/wiki/Privity_of_contract) means that contracts can only be enforced by the parties to that contract (although some jurisdictions have changed this with legislation). A defendant in a lawsuit against Twitter cannot assert an agreement between a third party and Twitter against Twitter. Disclaimer: IANAL