The digital coupon company Coupons.com will buy Yub, a San Francisco-based firm that promotes in-store sales through online offers, according to The Wall Street Journal.

Yub's technology allows users to link their credit or debit cards to online offers received via connected devices. However, Yub does not take a payment from these cards. Customers receive their reward when they use the registered card in-store, without having to print out coupons. The benefit to bricks-and-mortar retailers is that they track the link between online advertising and sales, Yub said.

Mountain View, Calif.-based Coupons.com offers digital printable coupons and digital paperless coupons that can be displayed on smartphones or linked to loyalty cards.

The addition of Yub will enable Coupons.com to offer better tracking of online offers and sales, the Journal said.

Based on a merger document, the newspaper said, Coupons.com will pay around $30 million for Yub; Coupons.com was valued at $1 billion and raised $200 million from venture-capital investors in 2011.

According to Bloomberg BusinessWeek, Coupons.com plans an initial public Offering in 2014.

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