Paul Mawhinney, founder of Record-Rama, Pittsburg, Pennsylvania, US, claims he has built the world's biggest record collection

He collected vinyls records. When the collection grew up to thousands, he created the shop Record-Rama. Then, he started to archive a copy of every sold album. In 2003, his music archive held 2 million items, twice the size of the Library of Congress similar collection. When the store was closed in 2008, there were 3 million items.

The Wikipedia page on Record-Rama is [1].