Nearly six years after the death of Microsoft co-founder Paul Allen, more valuable items from his estate are up for auction.

Christie’s auction house is managing the sale, dividing over 150 items into three auctions collectively titled “Gen One: Innovations From the Paul G. Allen Collection.”

The auctions feature a wide range of rare items, including vintage computer systems, iconic spacesuits, and groundbreaking art. Notably, a signed letter from Albert Einstein to President Franklin D. Roosevelt, warning of Nazi advancements in uranium-based weapons, is up for sale. Einstein’s letter sold for just under $4 million.

However, the “History of Computing” auction generated the most buzz. The lot includes an original Apple-1 computer, which sold for $352,800.

Apple-1 Computer from Late Microsoft Co-founder Paul Allen's collection
Image courtesy of Christie’s Auction House

Two supercomputers from the 1980s also drew significant interest from bidders, closing at $176,400 and $252,000.

Not all items are as expensive. Some vintage technology is valued in the tens of thousands, with a few pieces, such as midcentury typewriters and early issues of Popular Electronics, which sold for $4,410.

early editions of Popular Mechanics from late Microsoft cofounder Paul Allen's auction
Image courtesy of Christie’s Auction House

The auction sparked significant interest, following the success of a previous auction of Paul Allen’s art collection that raised $1.62 billion, making it the most valuable collection ever sold. Every item found a buyer, with bids coming in from over 30 countries.

It total, the second wave of Paul Allen’s collectibles auction brought in just under $17 million.

However, not all reactions have been positive. Many of the tech items come from the now-closed Living Computers Museum, which Allen founded in 2012. The museum allowed visitors to interact with vintage and modern technology. Allen hoped it would preserve the memory and achievements of early computer engineers.

“This is a travesty,” laments one Reddit user. Others express disappointment over the lack of plans for the museum after Allen’s death.

Despite the outcry, a representative from the Vale Group, a company founded by Allen, told The Seattle Times that the auctions are in accordance with his wishes.

Proceeds will go to charity, though the specific recipients have not been disclosed.

Paul Allen cofounded Microsoft with his lifelong friend Bill Gates. He passed away in 2018 after a nearly decade-long battle with cancer.

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Tanja Fijalkowski is Fiscal Report staff writer and Managing Editor based in the San Francisco Bay Area. She has a writing degree from University of California, San Diego. Over the course of her career, she has written and edited award-winning, Amazon top-selling books with a specialization in the topics of finance, investing, news, history, and science. She has over 4 years experience in the finance and insurance industry as an underwriter.