Apple’s rainbow logo was the symbol of the company from 1977 to 1998, and two of the signs that originally adorned the company’s Cupertino HQ are now being auctioned by Bonhams. They were given to an unnamed “longstanding Apple employee” when they were removed from the building.

The larger of the two signs measures 49×46 inches and is made from 1.5-inch thick foam with vinyl stripes. The smaller version is 36x33x6 inches, made from metal-backed fiberglass, again with vinyl colors.

Although generally thought of as the original Apple logo, the very first version was in fact an intricate drawing of Isaac Newton sitting under a tree with an Apple above his head.

The famous rainbow design was created a year later by Rob Janoff, who says on his website that it was the only logo concept shown to Steve Jobs, and was created in two weeks. The colors were designed to make Apple products look user-friendly, to make them attractive to school-children and to emphasize the Apple II’s unique color display.

Apple briefly switched to a translucent blue logo in 1998 before adopting a monochrome one later the same year, a white aqua version in 2001 and a Chrome variant in 2007.