Franklin Resources Inc. has a word for a $156 million demand by the heir of an early investor who says he was cheated out a 4,000-share bonus in 1973 -- extortion.

The money manager, which does business as Franklin Templeton Investments, and its 82-year-old retired chairman, billionaire Charles Johnson, say a lawsuit filed by the heir in January is a “scam” aimed at publicly embarrassing them after his attorneys failed to extort a payout for a block of stock he claims went missing in a treacherous coverup, according to a court filing.

The heir, Anthony Miele III, contends the firm and Johnson dodged his family members for decades when they tried to collect on the shares pledged to his father for loaning the firm $100,000 while it was struggling in a bear market in the early 1970s. Miele said in the complaint he never even learned about the stock until 2012, by which time title to the shares had been altered and the money was long gone.

Lawyers for Franklin are urging a San Francisco federal judge to sanction Miele’s attorneys for even bringing the lawsuit. His complaint omitted that his family’s law firm was given the share certificate in 1974, after his father’s death, and that Miele was paid $2 million by a family friend in 1990, “undoubtedly for signing over his Franklin shares,” according to Franklin’s court filing.

The two sides proposed Tuesday that the judge hold a July 2 hearing on the matter. David Marek, a lawyer for Miele with Liddle Robinson LLP in New York, had no immediate comment on the case when reached Monday. He didn’t immediately respond to a follow-up phone call on Wednesday.

$900 Billion

Franklin, which operates the San Mateo, California-based Franklin and Templeton mutual funds, manages almost $900 billion in assets for clients in 150 countries and had $8.5 billion in revenue in 2014. Johnson, who inherited the business from his father in 1957 at age 24, is now worth $6.1 billion and is the principal owner of the San Francisco Giants.

The firm hasn’t always been so successful. The roots of the current dispute go back 42 years to when Miele’s father, the owner of a New Jersey waste and sludge company and an Italian restaurant in Orange called Stash’s, allegedly loaned Johnson $100,000 to help pay for the acquisition of another investment firm that helped carry Franklin through a bear market while it was coping with the loss of 35 percent of assets under management.