Harris took to Twitter on Monday to denounce a tabloid story that claimed Swift had broken up with him because of infidelity.
“It's not going to be a 'happy ending' for everyone I sue for defamation of character for all these bulls*** stories bye bye,” the Scottish DJ/producer wrote.
According to the report, Swift, 25, dumped Harris, 31, after she found out he had visited a massage parlor where he cheated on her with a masseuse.
Swift has yet to comment, but she did favorite her beau's tweet.
The "Shake It Off" singer's rep also denied the report.