On November 28, 2005, it was officially announced that Maron's contract had not been renewed.His last Morning Sedition broadcast was on December 16, 2005, and the show was discontinued shortly thereafter.
He is particularly known for relentless on-stage exploration of his own relationships with family, girlfriends, and other standup comedians that he has known and befriended over his many years in the business.
In 2012, he provided the voice of Magnus Hammersmith in three episodes of Metalocalypse.
A comedy special, Marc Maron: Too Real, was released on Netflix on September 5, 2017.
From almost the first day of the liberal talk radio network Air America's broadcasts in 2004, Maron co-hosted Morning Sedition, a three-hour early-morning radio show with Mark Riley that aired weekdays from 6 am to 9 am Eastern time.
On February 28, 2006, Maron began hosting a nighttime radio program with Jim Earl as sidekick for KTLK Progressive Talk 1150AM in Los Angeles called The Marc Maron Show from pm until midnight PST.
The program was frequently delayed (sometimes for over an hour) owing to KTLK's contractual agreement to broadcast local sports events that would often go into overtime.
He also recorded half-hour specials for HBO and Comedy Central Presents as well as comedy showcases like the Cam Neely Foundation fundraiser, which also featured performers such as Jon Stewart, Denis Leary, and Steven Wright.
He frequently appeared in the live alternative standup series he had organized with Janeane Garofalo called Eating It, which used the rock bar Luna Lounge in New York's Lower East Side as its venue, from the 1990s until the building was razed in 2005.
His only major film credit for years was a small part credited as "angry promoter" in the 2000 Cameron Crowe film Almost Famous, in which he is first seen fighting with Noah Taylor's character and then yelling at and chasing after the main characters as they drive away on a bus, at which point he yells, "Lock the gates! His first one-man show, Jerusalem Syndrome, had an extended off-Broadway run in 2000 and was released in book form in 2001.
In 2009, he began work shopping another one-man show, Scorching The Earth.