A third safe harbor in the Act limits an OSP’s liability for system caching, in which an OSP makes a temporary copy of popular Internet material requested by a User so that the OSP can deliver that copy to subsequent Users, which can be done more quickly and efficiently than obtaining the original material for each subsequent User.42

This exemption applies to material (a) that is originally placed online by someone other than the OSP (the "Originator") and (b) that is transmitted from the Originator, through the OSP’s system, to a third party at that third party’s request. To qualify for the exemption from liability for the intermediate and temporary storage of such material, the OSP must meet the following conditions:

1. the OSP’s storage of the cached material must be made through an automatic technical process and must be for the purpose of providing the material to subsequent Users who request the material;
2. the OSP must transmit the cached material to subsequent Users without modifying its content;
3. the OSP must comply with any rules on updating the cached material that are specified by the Originator using a generally accepted industry standard protocol, as long as such rules are not used by the Originator to prevent or unreasonably impair system caching;
4. the OSP must not interfere with technology associated with the cached material that returns certain information to the Originator, as long as such technology doesn’t significantly interfere with the performance of the OSP’s system and is consistent with generally accepted industry standard protocols;
5. if the Originator has placed conditions (such as payment of a fee or entry of a password) on access to the cached material, the OSP must allow access to the cached material only to subsequent Users that have met such conditions; and
6. if the original material from which the cached copy was made has been removed or blocked and a copyright owner provides notice to the OSP (pursuant to certain "notice and take-down" provisions discussed below), the OSP must act expeditiously to remove or block access to the cached material that the copyright owner alleges is infringing.43

Safe Harbors for Transmission and Routing

A final safe harbor in the Act covers an OSP’s transmission, routing, or providing connections for material through the OSP’s system and for intermediate and transient storage of material in the course of such activity. In essence, this safe harbor covers an OSP’s activities in acting as a conduit for material travelling between other parties.

To qualify for this exemption, several conditions must be met:

1. the transmission of the material must have been initiated or directed by someone other than the OSP;
2. the activities covered by the exemption must be carried out through an automatic technical process and not by any selection of material by the OSP;
3. the OSP must not select the recipients of the material except as an automatic response to another person’s request;
4. the OSP must not make any copy of the material ordinarily accessible to anyone other than intended recipients and must not keep any copy for longer than reasonably necessary for the OSP’s transmission, routing, or connection; and
5. the OSP must not modify the content of the material as it transmits it through its system.44 Extent of Exemptions from Liability

The safe harbors of the Act provide somewhat different limitations on different types of remedies usually available for copyright infringement.