Wal-Mart Stores Inc.’s online marketplace, which launched in 2009, hosts products from more than 1,000 sellers and offers more than 10 million SKUs, roughly double the 5 million it offered in April, , Tri Huynh, director of business development for Walmart.com Marketplace told Internet Retailer today at the Shop.org Digital Summit in Dallas.

The retailer, No. 4 in the Internet Retailer 2016 Top 500 Guide, also is adding more than 1 million SKUs per month to its marketplace, he said.

Huynh provided an update on Wal-Mart’s marketplace business and offered a glimpse into its future plans. One of those plans is to investigate offering a fulfillment service to sellers similar to Fulfillment by Amazon, Huynh said Tuesday. “We are looking at fulfillment by Wal-Mart,” Huynh said. “We are looking at logistics and exploring that.” However, a Wal-Mart spokesman on Wednesday said Wal-Mart “has made no decision to explore or open up fulfillment services to third parties.”

Right now, merchants must be invited or submit a request to sell on the marketplace. There’s an even split between the two, he said.

Wal-Mart is looking for merchants with a proven record of good service and experience selling on marketplaces such as eBay Inc. and Amazon.com Inc. (No. 1 in the Top 500 Guide), Huynh said. Wal-Mart particularly seeks sellers of private-label products and electronics, apparel and accessories, and home and sporting goods, he said.

“We look at how well they are doing on other marketplaces,” Huynh said. “We don’t mind if they sell the same products on other marketplaces. That means it’s a good product.”

Walmart.com attracts about 80 million unique visitors a month, according to Huynh. In search results, the site shows marketplace items from outside sellers alongside its own products it sells directly. “We merge results into one listing page. The lowest price gets the buy box,” Huynh said. Wal-Mart takes a cut of the selling price depending on the product. The fee ranges from 6% for a PC to about 20% for jewelry, Huynh said.

After a merchant is approved to sell on the marketplace it can take as few as a couple days to get up and running, Huynh says, though it takes two to four weeks, on average. Wal-Mart marketplace sellers can work with vendors including ChannelAdvisor Corp. and CommerceHub, which help retailers sell on online marketplaces.

For now, Wal-Mart plans to operate the Jet.com Inc. marketplace separately, Huynh said. Although he said Wal-Mart “will look for synergy where it makes sense” between the two entities. Wal-Mart in August said it would by Jet.com for $3.3 billion in cash and stock and completed the deal earlier this month.

Jet CEO Marc Lore oversees Walmart.com and Jet.com, reporting to Wal-Mart president and CEO Doug McMillon. Lore’s title is executive vice president at Wal-Mart and president and CEO of Walmart eCommerce in the U.S.