This is a very good and complicated question. The U.S. House of Representatives has a custom and courtesy whereby the Speaker, the Majority Leader, the Minority Leader and the Whips may speak on the House Floor for “one minute” that is not timed. Although it is not typical, the Minority leader has invoked this before on various occasions throughout house history.

The filibuster was once part of House practice, as were other dilatory tactics. Speaker Thomas Brackett Reed of Maine in the late nineteenth century devised several rules of procedure to limit the ability of the minority to prevent the majority from working its will.

One common method in the 1870s and 1880s was the "silent quorum" or "silent filibuster." Under the House rules of the time, a quorum of members, a majority, had to be present in order for business to be conducted. But in order for a member to be counted as "present," he had to affirmatively answer when his name was called by the clerk. If the member refused to answer, even if physically present in the chamber, he was marked absent. Since, invariably, some members actually were absent — either ill, traveling, or otherwise unavailable — it usually wasn't difficult for a minority, by remaining silent during the roll call, to prevent the majority party from reaching the necessary quorum. Thus, the will of the majority was thwarted without an actual vote having to be taken.

This tactic enraged Reed. When he was elected Speaker at the beginning of the 51st Congress in 1889, conditions were ripe for change. For the first time since 1874, one party controlled the White House and both houses of Congress. Reed wanted to break the silent filibuster.

The new Speaker's chance came on January 29, 1889, on a motion over a disputed election. Only 163 members affirmatively answered the quorum call, two short of the necessary 165. Instead of simply leaving it at that, however, Reed turned to the clerk of the House and directed him to "record the names of the following members present and refusing to vote." Reed then began reeling off the list of names of Democrats present in the chamber who had refused to answer when their names were called. Democrats militantly objected, calling Reed a “tyrant” and “czar,” but Speaker Reed held firm, even though the debate over this “revolutionary” rules change lasted three days. Finally, the Republicans were able to muster a quorum without any minority members, and Reed’s ruling was approved.

Since that time, the House of Representatives has become the legislative body that is most responsive to its majority. Prior to Mr. Boehner’s speech on June 26th, the only instances of extending debate time that have become House precedents include Dec.18, 1998, when Minority Leader Richard Gephardt of Missouri was recognized for three minutes and consumed twelve, and when Majority Leader Tom DeLay of Texas on May 18, 2004, extended a one minute to two minutes. There have been numerous times when various members of the leadership have extended their time, such as when the Minority Whip and Majority Leader engage in weekly colloquies about upcoming business. But as there are no objections or points of order raised against such extensions of time by the leadership, these events are not officially precedent.

On June 26th, Minority Leader Boehner was yielded 2 minutes, but continued speaking after his time had expired. A parliamentary inquiry was raised; pointing out that the Minority leader had been speaking at that point around 20. “I know we have this ‘magic’ minute that gives leaders a lot of extra time to speak, but I'm just wondering if there is some limit under the rules on the time that a leader may take, even though the time yielded was not 20 or 30 minutes.”

The Speaker pro tempore responded, “It is the custom of the House to hear the leaders' remarks.” A further parliamentary inquiry was raised: “I know it is the custom of the House to give a little extra latitude. Is there any outside limit to the amount of time a leader might take? And do we have historical records that might be broken tonight? Or is this an attempt to try to get some people to leave on a close vote?”

The Speaker pro tempore responded, “It is the custom of the House to hear the leaders' remarks.”

The Minority Leader continued to speak for about an hour. When this extension of time was so noted from the Floor, with a question of the Speaker, “Could you tell us how much time he consumed?” the Speaker pro tempore responded, “The gentleman used a customary amount of time.”

Since the late nineteenth century, the Minority Leader’s extension of time on June 26th, 2009, has been the longest such speech noted through a parliamentary inquiry. As such, this may set a precedent in the House for a leader’s “customary amount of time.”