Three leading news organizations say they didn't transmit information about the Federal Reserve's decision not to taper before a designated embargo time last Wednesday.
Their statements come as the Federal Reserve says it is contacting news groups to discuss the rules surrounding lockup procedures and the release of market-moving information from the Fed's headquarters in Washington.
A Thomson Reuters spokesperson emailed a statement to CNBC on Wednesday saying, "We did not release any information before the embargo time of 2 p.m.—this covers all distribution, inclusive of information distribution outside the lockup room before 2 p.m. We did not release information outside the lockup room before 2 p.m."
Two other organizations said that they did not transmit data outside the lockup room before the deadline. A spokesperson from Bloomberg News said that organization did not transmit information before 2 p.m. And Michael Scarchilli, editor-in-chief of the publication The Bond Buyer, also said his organization did not transmit information before the deadline.
However, a spokesperson for Dow Jones declined to say whether or not the organization transmitted data, instead emailed a statement to CNBC saying, "We will continue to work with the Fed cooperatively to report in full accordance with their desires."
A second organization also declined to say whether or not it transmitted data out of the lockup room before the deadline. Instead, Market News International, which is owned by the Deutsche Boerse Group, sent CNBC this statement: "MNI follows the rules set by the Fed as we do with all data releases."
So what exactly were those Federal Reserve lockup rules? Were organizations allowed to transmit information out of the room before 2 p.m. or not? The Federal Reserve won't say—a Fed spokesman declined to answer that question from CNBC.
A leading expert on millisecond level trading says he is focusing his attention on a certain type of news organization—those that offer so-called low latency services to feed market-moving data at high speeds directly into computerized trading systems.
Eric Hunsader, founder of the market analysis firm Nanex, says that's because he saw simultaneous reactions to the Fed's announcement last week in trading in New York and Chicago. That would be theoretically impossible if the information was released from the Fed's headquarters in Washington.
In theory, the trading reaction should have begun in New York several milliseconds before it began in Chicago, because information takes several more milliseconds to travel the longer distance.
"The very first thought I had when I looked at this closely was this is a low latency service," Hunsader said. "We have just very recently looked closely at some of these low latency releases and seen that they are indeed at the same exact millisecond. We have immediate history behind it."
(Read more: No taper! Did Bernanke fool the Street?)
Working off of a list provided by the Fed of news organizations participating in last week's lockup, CNBC contacted each of the news organizations that offer low latency data services to ask whether they transmitted any data out of the Fed's lockup room.
A key question is whether or not any organization transmitted information out of the lockup room and into its own computer system before 2 p.m. If that was done, the data could have been moved to computer servers near Chicago before 2 p.m. and publicly released the information from there at precisely 2 p.m.—enabling subscribers of that data service to get the information millisec——onds before others in Chicago relying on transmissions from the Federal Reserve in Washington to arrive.