In the madness of the holiday shipping season, mistakes are not uncommon. Sometimes, lucky shoppers find themselves on the winning end of those mistakes, like when you get 99 extra knives or when a retailer sends four iPods instead of one. So what’s an honest consumer to do?

To put it simply: you can keep it. According to the Federal Trade Commission, you have a legal right to keep unordered merchandise and consider it a free gift. That’s because federal law prohibits mailing unordered merchandise to consumers and then demanding payment.

This question came up recently for Consumerist reader M., who says she ordered an iPad for her mother during Target.com’s Black Friday promotions. Her mom ended up with two iPads instead of one, and she asked Consumerist what she should do — how could she trust that the returned item would be put back into Target’s inventory if she brought it to a store? Would she get an accidental refund on the item if she initiated the return process online?

In these situations, Target’s first recommendation is for customers to call a Target.com service rep at (800)591-3869, a spokesperson told Consumerist, noting that guests’ first option is to keep or donate the extra item.

“If a guest chooses not to do that, we have an ‘exceptions process’ where they can return the product in the mail,” the spokesperson explains. “They should speak with a Target online guest service representative for instructions, and then return the item to us with all order information removed from the package.”

In general, though you’re not legally obligated to tell the seller, if your conscience is pushing you in that direction, the FTC suggests that you notify the seller and offer to return the merchandise, so long as the seller is the one who will pay for all of the return shipping.

“Give the seller a specific and reasonable amount of time (say 30 days) to pick up the merchandise or arrange to have it returned at no expense to you,” reads the FTC’s FAQ on this topic. “Tell the seller that you reserve the right to keep the merchandise or dispose of it after the specified time has passed.”

Consumerist reader M. is far from alone in receiving merchandise she never asked — or paid — for:

• There was the time Williams Sonoma sent a customer 99 knives though he only wanted one;

• The Consumerist reader who received an Amazon package that was intended for a person who previously lived at his address;

• The Lululemon customer who received 19 extra running hats in the mail and was told to keep them all;

• The shopper who ordered one iPod Touch from Walmart and instead, got five devices in the mail;

• And then there was the year Best Buy seemed intent on sending folks five iPads instead of only one — not once, but at least twice, to two different shoppers.

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