Microsoft, IBM Stocks' Brief Premarket Plunges Were 'correct' Trades--FINRA Spokesperson

The one-off trades that briefly sent Microsoft Corp.'s stock tumbling 12% in premarket trade Friday, and International Business Machine Corp.'s stock plunging 11%, were "correct" trades and will not be erased, a FINRA spokesperson told MarketWatch. The trades were made via the FINRA/Nasdaq Trade Reporting Facility (TRF). "They were both premarket, and both odd lots, and therefore don't need to be within the National Best Bid and Offer [requirement]," a FINRA spokesperson told MarketWatch. The NBBO is the Securities and Exchange Commission rule that requires brokers to guarantee the best available ask or bid price when the execute trades for customers, according to Nasdaq. In other words, someone is just out of luck, and someone else is feeling very lucky.