Diane Hunt, a Yahoo spokeswoman, said the discussions with the F.T.C. had "nothing to do with advertising profiling."
A Yahoo spokeswoman said the company did not discuss "rumors and speculation."
Even so, a Yahoo spokeswoman said Yahoo had not given Enron any information about anyone who posted a message.
A Yahoo spokeswoman, Gaude Paez, did say, however, that click fraud is a serious, but manageable, challenge.
A Yahoo spokeswoman said Yahoo executives were unavailable to comment on Google's new initiatives Friday.
"If an advertiser prefers to have a relationship with them, that's fine," said Gaude Paez, a Yahoo spokeswoman.
"Yahoo has a long and successful history in personalization," said Helena Maus, a Yahoo spokeswoman.
A Yahoo spokeswoman declined to comment.
Settlement talks were completed late Sunday night, according to a Yahoo spokeswoman, Nicki Dugan.
Mary Osako, a Yahoo spokeswoman, said the company complied with the subpoena "on a limited basis."