American Top 40 (fictional)

Censorship, offensive songs and affiliate standards
Casey Kasem and Watermark's policy regarding putting American Top 40 together was to always play the forty most popular songs in the United States and never to ban a record from the countdown. However, whenever songs with potentially offensive lyrical content made the top 40, Watermark would send out memos to affiliated stations alerting them of the presence of that song in the countdown and sometimes provide stations with suggestions on how to edit the song out of their AT40 broadcasts.

When the show became part of Premiere Networks since 1998, a few stations airing AT40 (especially in most countries around the world) were opted to either change versions of each songs or skipped some portions of the show due to various reasons.

Offensive content
In 2001, Dollhouse's "Adorame" debuted on AT40 using a slightly suggestive version, despite a more radio-friendly version of the song being available.

In 2006, "When the Sun Goes Down" by Arctic Monkeys, peaking at #40, was edited to remove the words "scummy", "scumbag" and "fucking".

Disco and rap
In the late-1990s/early-2000s, three stations carrying American Top 40 had to carry customized versions of the show. Rhythmic Top 40 station KFOR-FM in aired the show with country, rock and adult contemporary songs mentioned but not played and replaced with dance/rhythm-leaning extras (this included a few times in which the #1 song was mentioned but not played). KAHT-FM in aired AT40 with songs that did not meet the station's Hot AC format omitted. WPRT-FM in aired AT40 with the rock/country/adult contemporary songs omitted and replaced with rhythmic/dance-leaning extras.