Service of process of IPR Petitions can become "lost in the shuffle" if correspondence addresses aren't updated

Once an IPR petition is served, the patent holder has a non-extendable three month period to prepare a preliminary response. All the Petitioner is legally required to do is to serve the Petition to the correspondence address of record. Thus, if that correspondence address hasn't been updated in years -- and the Petition winds up being served to an address of a patent prosecution firm that is no longer in existence, the client may not even be aware of the proceeding.

​The moral of the story:  Always make sure the correspondence address with the USPTO is up to date.  
More information on these types of problems can be found here:

http://www.lexology.com/library/document.ashx?g=7379c6c0-bd83-4bc0-b35d-569ff3464e0e