Star bond fund manager Jeffrey Gundlach and his inner circle plotted to destroy Trust Company of the West by forming a competing firm while they were still employed by TCW, a TCW attorney said in closing arguments in a trial over alleged theft of trade secrets.

They essentially stopped working for TCW, and worked against TCW, attorney John Quinn told jurors on Tuesday.

And they did all these things while drawing their very generous paychecks.

Quinn's presentation in a Los Angeles courtroom marked the final day of arguments in the high-stakes trial with hundreds of millions of dollars at stake.

Attorneys for Gundlach are expected to deliver their own closing argument later on Tuesday.

TCW, a unit of French bank Societe Generale (SOGN.PA), fired Gundlach in December 2009 and sued him a month later, accusing him of stealing trade secrets, plotting to form a new company using TCW proprietary information, and gutting the firm of its entire mortgage-backed securities team.

Gundlach fired back with a counter-lawsuit, alleging that his former employer owed him hundreds of millions of dollars in compensation and had secretly plotted to fire him while he was still chief investment officer.

In the weeks following his termination, Gundlach went on to form DoubleLine Capital, along with three of his co-defendants in the case. Roughly 45 TCW employees, largely from the mortgage-backed securities group, followed.

The warm courtroom was packed, with audience members sitting shoulder to shoulder. Jury deliberations are expected to begin on Wednesday morning.

The case in Superior Court of California, County of Los Angeles is Trust Co of the West v. Jeffrey Gundlach et al, BC429385.