It was recently reported that David Letterman’s program The Late Show with David Letterman invited his long-standing arch rival Jay Leno to appear on the show in advance of Letterman retiring from TV in May.

The feud between the two late-night titans is almost 25 years old, but there might still be some simmering feelings between the two. Letterman’s TV company, Worldwide Pants, which produces The Late Show for CBS, is probably banking on it.

Both Letterman and Worldwide Pants declined to comment on the report. Last week, Leno dismissed a question about the possible offer to appear on The Late Show while addressing an audience at the National Association of Television Program Executives conference in Miami, according to the report. “I haven’t heard that,” Leno was quoted as saying. “I’ll have to check into that.”

A potential appearance from Leno could be a ratings bonanza for CBS and The Late Show before Letterman leaves for good.

The rivalry between Letterman and Leno became the stuff of legend after NBC picked Leno over Letterman to succeed Johnny Carson as host of the Tonight Show in 1992. An irate Letterman, who most had expected to take over the Tonight Show chair, launched his own late-night program on CBS that same year to air opposite Leno.

The Tonight Show had another messy shakeup in 2009, when NBC offered the hosting job to Conan O’Brien, as Leno launched his own 10 p.m. variety program. Leno’s show was a ratings disaster, and O’Brien lasted just 8 months at the Tonight Show before Leno requested his old job back. Letterman made unapologetically gleeful hay of the debacle on his own show for months.

Jimmy Fallon became the new host of the Tonight Show last year and Stephen Colbert will take over The Late Show from Letterman in September.