Amazon.com Inc. is designating products sold by certain companies as “top brands,” a test that if widely implemented could ease tension between the online retail giant and big-name companies used to favorable positioning at brick-and-mortar retailers.

Shopify Inc. shares continued their rally Aug. 1 after the Canadian e-commerce company reported second-quarter sales that beat analysts’ average estimate and gave a more optimistic full-year outlook.

Kroger has unleashed a flurry of initiatives to ensure it won’t get thumped in a post-Amazon-buying-Whole-Foods world, but its biggest gamble is a partnership with British online grocer Ocado Group to build as many as 20 automated grocery warehouses in the United States.