Dive Brief:

• Wal-Mart Stores Inc.’s warehouse club segment, Sam’s Club, is piloting a subscription e-commerce program. Target recently launched one, Amazon has had one for a while, and smaller e-retailers like Birchbox base much of their activity on one.

• Sam’s Club’s subscription service costs $45 a year and offers free shipping on items that are automatically sent each week or each month, but, unlike Target and Amazon, doesn’t offer discounts.

• The move is the latest e-commerce advance by Sam’s Club, which has also recently revamped its site search tool and begun offering some crossover availability with walmart.com.

Dive Insight:

A spokesperson at Sam’s Club says the new subscription program isn’t a direct reaction to Amazon, but it's a little hard to believe that there's nothing to that. Certainly there's a lot of experimentation with annual membership fees, shipping perks, and other options for customers happening in e-retail right now. The things that work will stick around — and get copied — no doubt. These are intriguing developments for Amazon, too. As more retailers offer memberships and bonuses for customers who join, it may become more difficult for Amazon to raise its Prime membership, as it has said it might.