If you're lucky enough to buy Google Glass during the futuristic headset's beta program, you had better be happy with your purchase. Google's terms of sale for the Google Glass Explorer Edition forbids buyers from reselling, loaning, transferring, or just giving the device to any other person without Google's approval.

Google may even remotely deactivate the device if it finds its buyer is no longer in control of it. From the terms of sale:

You must be 18 years or older, a resident of the United States, and authorized by Google as part of the Glass Explorer program in order to purchase or use Glass Explorer Edition. Unless otherwise authorized by Google, you may only purchase one Device, and you may not resell, loan, transfer, or give your Device to any other person. If you resell, loan, transfer, or give your device to any other person without Google’s authorization, Google reserves the right to deactivate the Device, and neither you nor the unauthorized person using the Device will be entitled to any refund, product support, or product warranty.

This provision is specific to Glass Explorer, an early adopter program in which developers and others selected by Google may pay $1,500 for the device. We've asked Google if a similar restriction will be placed on Glass when it becomes generally available, but the company declined to comment.

The terms of sale do indicate that Google will place at least some resale restrictions on Glass at general availability. The restrictions we quoted above came in a "Device Specific Addendum" that applies to the Glass Explorer Edition. In an earlier paragraph apparently referring to all versions of Glass, Google says, "You may not commercially resell any Device, but you may give the Device as a gift, unless otherwise set forth in the Device Specific Addendum." Thus, it sounds like people who buy the glasses at general availability later this year won't be forbidden from lending or giving the device away. Google also makes no mention of remotely deactivating the device except in the addendum specific to the Explorer edition (and in an unrelated section regarding lost devices).

As for how Google would know a device has been transferred, we presume one tipoff would be if it was switched from one Google user account to another.

Our friends at Wired reported on the bizarre restriction placed on the Glass Explorer Program yesterday. It has already affected at least one early purchaser of Glass. One man attempting to sell his Google Glass on eBay halted his auction after the purchase price had gone up to an astonishing $90,000. The man, "Ed," is disappointed about losing a big payday but is hoping he'll still be able to purchase the device and use it himself. “I’m willing to fork up the $1,500 for it,” he told Wired.

Companies placing restrictions or nondisclosure agreements on early versions of products released solely to developers for the purposes of building third-party software is nothing new. This goes a bit beyond that, however. Glass's hardware specifications are not a secret like the specifications of a game console might be during its prototype phase. Glass is also being sold for $1,500, so it's priced like a consumer product even if it's just a prototype. And though Glass is being sold in only limited quantities, it's not restricted to developers—Google is selling it to a bunch of random people who responded to a query on Twitter. Those people presumably weren't asked to sign any agreements, although they could look up Google's restrictions in the terms of sale available on the Glass website.

Ed is one of those who gained access to the Glass Explorer Program through Twitter. "Because the only correspondence Ed has had with Google is the initial tweet about his acceptance into the program, he had no idea he wasn’t allowed to sell his Google Glass, which he had been authorized to purchase for $1,500 in the coming weeks," Wired wrote.