After Facebook's (FB) Instagram announced in a blog post that it is adding in-app checkout, RBC Capital analyst Ross MacMillan explained that he views the risk to Shopify (SHOP) being that native Instagram Checkout could take some gross payments volume share in the future, some of which would have been Shopify's. As it stands today, merchants can link Instagram as a channel to their Shopify platform and transactions occur through the Shopify checkout, which would generate payments volume and revenue, assuming that merchant uses Shopify Payments, said MacMillan. However, he added that he thinks volumes from Instagram purchases are "very small" today. MacMillan has an Outperform rating on Shopify shares.