? 
I have sent an email to the lawyer saying that I have no intention of keeping information about the company in sajha that is not verifiable and possibly defamatory to the company.
In the email I included 3 links to other sites which were carrying the same info that was posted in sajha. I implied these could be possible sources of the info posted in sajha. One of which happened to be Google Groups - I wonder if they went after google too...
Finally I'm glad that this happened because upon some research I have found the following info, which protects discussion site from postings made by other users. Taken from http://chillingeffects.org/defamation/faq.cgi
Question: Can an ISP or the host of the message board or chat room be held liable for
defamatory of libelous statements made by others on the message board?
Answer: Not in the United States. Under 47 U.S.C. sec. 230(c)(1)
(CDA Sec. 230): "No provider or user of an interactive computer service
shall be treated as the publisher or speaker of any information
provided by another information content provider." This provision has
been uniformly interpreted by the Courts to provide complete protection
against defamation or libel claims made against an ISP, message board
or chat room where the statements are made by third parties. Note that
this immunity does not extend to claims made under intellectual
property laws.
board host delete postings that someone tells him/her are defamatory?
Can the ISP or message board delete postings in response to a request
from a third party?
Answer: No, they are not required to delete. 47 U.S.C. sec. 230
gives most ISPs and message board hosts the discretion to keep postings
or delete them, whichever they prefer, in response to claims by others
that a posting is defamatory or libelous. Most ISPs and message board
hosts also post terms of service that give them the right to delete or
not delete messages as they see fit and such terms have generally been
held to be enforceable under law.