(Reuters) - Pacific Investment Management Co said former bond manager Bill Gross' abusive conduct and effort to sabotage colleagues he deemed disloyal gave it "good cause" to oust him, and not pay any of the more than $200 million of damages he now seeks in a lawsuit.
In a Monday filing with the California Superior Court in Santa Ana, Pimco also said Gross acted unprofessionally when he "abruptly quit" the firm in a handwritten scrawl left behind in the middle of the night for colleagues to find the next morning.
The Newport Beach, California-based firm's response ratchets up the legal dispute that began last October when Gross sued Pimco, accusing executives of plotting to oust him from the firm he helped found more than 40 years ago and divide up his bonus.
Patricia Glaser, a lawyer for Gross, said in response that the lawsuit targeted a "money grab" by Pimco executives who wanted "a bigger piece of the pie - the piece that based on his contract belonged to Bill."
Gross, a billionaire, is now a portfolio manager for Denver-based Janus Capital Group Inc, and has pledged to donate proceeds from the lawsuit to charity. Janus said the lawsuit is a personal matter for him.
Pimco is a unit of German insurer Allianz SE.
Gross left Pimco in September 2014 amid negative reports about his leadership and weak returns at Pimco Total Return, once the world's largest bond fund. He now runs the $1.3 billion Janus Global Unconstrained Bond fund.
In its filing, Pimco said Gross' own "self-destructive behavior" would have justified his firing, and included his "breaking commitments to abide by management decisions, trying to sabotage the careers of the former CEO and others he suspected of disloyalty, and treating his colleagues abusively."
It also said Gross had no employment agreement, and acknowledged in a meeting the day before he left that he would forfeit any potential bonus if he quit that month.
Pimco attached to the filing a handwritten resignation note that it said Gross left behind before leaving its offices for the last time, and which it did not find until after Janus announced his hiring on Sept. 26, 2014.
The note read: "TO: CEO, PIMCO.... This letter will confirm my resignation from PIMCO as of Sept 26th, 2014 at 6:29 AM PST." It was signed "William H Gross."
The case is Gross v. Pacific Investment Management Co et al, California Superior Court, Orange County, No. 2015-00813636.
Reporting by Jonathan Stempel in New York; Editing by Clive McKeef, Toni Reinhold