Y-combinator-backed gift card marketplace Cardpool has been acquired by Blackhawk Network, a subsidiary of Safeway and one of the largest distributors of gift cards in the world. Financial terms of the deal have not been disclosed.

Cardpool, which launched in 2010, buys people’s unwanted gift cards, and sells gift cards at large discounts. They judge the buyback and selling amount by how desirable the cards are. For example, you can sell a BestBuy’s gift card, which is highly desirable, to CardPool for 90 percent of its value. And on CardPool’s site, you can find a Best Buy gift card for 5 percent off its original value. On the other hand, 1-800-Flowers’ gift cards, which are not as popular as Best Buy’s cards, are discounted by 30 percent on the site.