Stuart Clarke and David Lieberman were fictional characters showcased in which comics universe?
Marvel
Title: Microchip (comics)
Passage: David Linus "Microchip" Lieberman (often known as Micro) is a fictional character appearing in American comic books published by Marvel Comics.  He was an ally of The Punisher for many years and assisted the Punisher by building weapons, supplying technology and providing friendship.  In more recent publications, Microchip gradually evolved from the Punisher's friend to a bitter villain.
Title: Rampage (Marvel Comics)
Passage: Stuart Clarke is a comic book character in the Marvel Comics universe, an ex-supervillain who first fought as Rampage against the short-lived Champions team.  He is an ally of the Punisher, replacing Microchip.
Title: David Lieberman Artists' Representatives
Passage: David Lieberman/Artists’ Representatives is a performing arts management agency located in Newport Beach, California, United States.  DLAR was founded in 1985 to support artistic expression in the creation of live performance experiences.  DLAR began with a single artist and over the years has grown to manage 8-10 internationally known artists touring worldwide.  In addition to its tour management efforts, David Lieberman/Artists’ Representatives focuses on the development and production of its artists’ works.
Rampage (Marvel Comics) Microchip (comics)