The legal battle between Lyft and its former COO is shaping up to be a long, ugly fight. The on-demand car company has accused Travis VanderZanden of stealing tens of thousands of secret company documents before he joined Lyft's main competitor, Uber. Now VanderZanden has fired back in a new court filing, saying he was plotting with Lyft's board of directors to dispose of the company's CEO before leaving the startup.

Uber made a small splash last month when it hired Lyft's former COO Travis VanderZanden. Kara Swisher said the move "will surely increase tensions between Uber and Lyft, which are now pretty tense as it is." And she was right: Lyft is suing VanderZanden, alleging that he took company secrets along with him to Uber.