Doesn't matter whether the emails were marked or not. Moreover that doesn't help her being an originator of Classified Information.
She also sent classified information to Sidney Blumenthal, a former Clinton White House operative banned by the Obama White House. An analysis by The Federalist of e-mails released by the State Department late Monday
shows that scores of e-mails sent by Clinton contained highly confidential national security information from the beginning, even if they weren’t marked by a classification authority until later.
That is because under federal law, information is classified by nature, not by marking. As a result, federal classification authorities deemed that the information was classified the very second it originated, even if it was not marked as such until August 27, 2015.
Also worthy of note is the fact that Hillary’s message is the only content in the entire document that is redacted and marked as classified. This means that she was not merely a helpless, passive recipient of classified national security information; she was the originator. And not only did she intentionally originate the classified information,
she intentionally disseminated it via an unsecured, unsanctioned private e-mail server.
Hillary Clinton’s campaign team has repeatedly tried to dodge responsibility for her distribution of classified information
by claiming the information was not marked at the time. However, the nature of Hillary’s secret, off-books private e-mail scheme made it impossible for government authorities to mark as classified any information that originated on Hillary’s private server, since they had no access to it. In fact, one of the newly released e-mails shows that the agency’s IT department had no knowledge of her private e-mail address and server scheme......snip~
Hillary Intentionally Originated, Distributed Classified Material