This undated photo provided by Christie’s Auction House in 2013 shows an “Apple 1” prototype computer, built in 1976, accompanied by an operation manual and schematic as well as a photo of its inventors, Steve Wozniak and Steve Jobs. (Christie’s Images Ltd. via AP)

A vintage Apple I computer, one of only about 200 first-generation desktop computers built by Steve Jobs, Steve Wozniak and Ron Wayne in 1976, can fetch six figures.

Assuming, that is, you know you have one in your possession.

A Silicon Valley recycling firm that specializes in computers, lab equipment, test equipment and semiconductors suspects a local woman was unaware that she had a valuable piece of tech history in her possession when she dropped off two boxes of old electronics that she’d gathered while cleaning out her garage in April.

“She said, ‘I want to get rid of this stuff and clean up my garage,’ ” Victor Gichun, vice president of Clean Bay Area, told the San Jose Mercury News. “I said, ‘Do you need a tax receipt?’ and she said, ‘No, I don’t need anything.’ ”

Gichun told the Mercury News that the woman said her husband had died several months earlier, prompting her to clean out her home. In hopes of helping her through a hard time, there’s something he’d like to give her, but he has no way of contacting the mystery donor.

“We are looking for her to give her $100,000,” Gichun told the Mercury News.

That’s half the amount the recycling firm received after selling the computer to a private collection, according to the Mercury News. Firm policy, the Mercury News reported, is to share proceeds with donors down the middle.

The $200,000 sale price is actually on the low side for one of the highly collectible computers: Last year, a working model was auctioned for $750,000 by Bonham’s — $905,000 including commission. Two years ago, another Apple I sold for nearly $675,000.

It took workers at the Silicon Valley warehouse a few weeks to sort through the woman’s boxes. When they finally did, they were shocked.

“We really couldn’t believe our eyes,” Gichun told NBC affiliate KNTV. “We thought it was fake.”

“It was the first computer that Steve Jobs and Steve Wozniak created in their garage, and it was sort of this breakthrough in personal computing,” David Crandall, a computer science professor, told KNTV-TV.

It’s not too late for the mystery woman to pick up her $100,000 check. She just needs to show up at the company’s warehouse in Milpitas, Gichun told the Mercury News.

“To prove who she is,” he said, “I just need to look at her.”

This post has been updated.

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