"We are indebted to all who serve. Discrimination against anyone holds everyone back," Cook tweeted. He ended with the hashtag "Let Them Serve."
Google (GOOGL) - Get Alphabet Inc. Class A Report CEO Sundar Pichai and Facebook (FB) - Get Facebook, Inc. Class A Report CEO Mark Zuckerberg also tweeted their disappointment in the president's decision.
Earlier today Trump tweeted that he consulted with his generals and other military experts and determined that the U.S. would ban transgender people from serving in any capacity in the military, because the U.S. could not bear the medical costs and "disruption" he claims transgender people will cause.
Apple's shares rose 0.5% to $153.53 on Wednesday.
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