Marc Lore, CEO, Walmart eCommerceScott Mlyn | CNBCThe leader of Walmart’s U.S. e-commerce business, Marc Lore, is leaving the big-box retailer, according a filing on Friday by the retailer.Lore joined the company in 2016 when Walmart acquired the start-up he co-founded, Jet.com, for $3.3 billion. With the pricey acquisition, the legacy brick-and-mortar retailer sought to jumpstart its digital business and play catch-up to rival Amazon. The deal was seen by investors and analysts, in part, as a way for Walmart to gain the digital savvy of Lore and his team. Lore, a serial entrepreneur, had deep experience in e-commerce and sold his former company, Quidsi, the parent of Diapers.com, to Amazon. In an 8K filed on Friday, Walmart said Lore notified the company on Thursday that he would retire from his position at the end of January. He will serve as a strategic advisor to Walmart through September, the company said. This story is developing and will be updated.