Alpaca will begin charging borrow fees on overnight short positions for the month of June 2021 and onward as part of its efforts to provide world-class brokerage services and APIs. Borrow fees are charged by a brokerage firm to a client for borrowing shares, typically incurred when short positions are carried overnight. Short selling involves borrowing a stock, selling it, and buying it back to return to the lender. Alpaca will resume pass-through charges from its clearing firm to clients starting June 2021 after waiving fees between February to May 2021 during its transition period. Clients holding short positions as of Friday settlement dates will incur stock borrow fees for the next three days, regardless of the actual number of shares borrowed.