Shares of Netflix, known for its original shows such as “House of Cards” and “Orange is the New Black”, plunged about 15 percent after the bell, before clawing back to trade down 2.4 percent. U.S. credit and debit card companies have been shifting to chip-enabled cards ahead of the Oct. 1 deadline mandated for the switch. For Netflix, the switch meant that many of the older cards on its file no longer worked as the companies gave new cards to their customers, leading to “involuntary churn,” as Chief Executive Reed Hastings put it in a letter to shareholders.