A DMCA Counterclaim or Counter Notice is submitted in response to a valid DMCA Takedown by the accused infringing website owner (ISP subscriber client). It is submitted to the service provider (OSP/ISP) after the DMCA Takedown has been submitted and after the content has been removed.
The DMCA Counterclaim process occurs after the initial DMCA Take down has been completed (removal of claimed infringed content).
A counter claim or counter notice cannot be used to defend against or as a defense to a Takedown Notice.
A counter claim or counter notice cannot be used to delay the process of a Takedown Notice.
Once the service provider (ISP/OSP) has received a valid DMCA Counterclaim or Counter Notice they must wait 10-14 days before they re-activate or allow access to the claimed infringing content. Unless the copyright owner (complainant) files a order in court against the infringing site owner, the defendant (ISP / OSP subscriber) and demonstrates the order to the ISP/OSP.
http://www.copyright.gov/legislation/dmca.pdf - page 12