Trump has been involved in literally thousands of lawsuits, many of which were filed against Trump because he stiffs the people who work for him, but in at least one case, Trump was stiffed by Trump.
The Republican presidential nominee attached his name to a mortgage company in 2006 which folded along with the rest of the mortgage industry, and then Trump sued his own company over unpaid rent at his own building.
By February 2007, Trump Mortgage stopped paying rent to its landlord, 40 Wall Street LLC—which Trump owned, through the Trump Organization. What happened next? One Trump company took the other to court. In July 2007, 40 Wall Street LLC petitioned New York County Civil Court for $57,367.95 (the unpaid rent plus $450 in legal fees) and asked for permission to evict Trump Mortgage from its 25th-floor space. After Trump's Trump Mortgage LLC failed to respond to the petition, Judge Debra Samuels ruled in favor of the Trump-owned 40 Wall Street LLC, and the struggling mortgage company, which went out of business in 2007, was booted out of Trump's own building.
Without more detail its hard to say why Trump would sue his own company for a measly $57,000. We could speculate, but in any case that does not seem like something a real billionaire would do.
After Trump Mortgage failed, Trump licensed his name to Trump Financial which, not surprisingly, also failed.
Everything Trump touches turns to shit.