The actor, who portrayed Mr Wilhelm in the hit US comedy series died on Tuesday at his home in Los Angeles of complications from cancer.
His wife Patricia Crowder Herd confirmed the news of his death to The Hollywood Reporter.
As well as a successful TV career, Richard also starred in many films, including The China Syndrome with Jane Fonda and Michael Douglas, and All The President’s Men alongside Robert Redford and Dustin Hoffman.
More recently he played Roman Armitage in Jordan Peele’s award-winning horror, Get Out (2017).
In Seinfeld he played George Costanza’s (Jason Alexander) supervisor during Costanza’s time as assistant to the travelling secretary of the New York Yankees.
He made his first appearance in the show in 1995 and reprised the role a total of 11 times until the series finale in 1998.
Other TV credits included Star Trek, V, M*A*S*H, Dallas, ER, The OC, and Desperate Housewives.
Tributes have been paid on Twitter by those that knew and worked with the star...
He is survived by his wife, daughter Erica, son Rick, and stepdaughter Alicia.