3M Company, maker of the ubiquitous Post-it note, has been sued by an inventor who says he first conceived of the sticky message products.
Alan Amron, 67, filed suit in a federal court in Florida seeking at least $400 million in damages and interest from 3M, according to court documents seen Friday.
In his suit, Amron, who claims to have 39 US patents, said he had invented the product in 1973 and called it "Press-on-Memo", but without filing a patent.
However 3M has stuck to it position that Post-it, one of its most famous brands, was invented by its scientists Arthur Fry and Spencer Silver.
The St. Paul, Minnesota-based company began marketing the product in 1977 and sales of the little notes took off in 1980.
Amron sued 3M in 1997 claiming he was the Post-it inventor. The two parties settled the lawsuit but the terms of their deal were not published.
In his new suit, Amron said that the two companies had agreed in the settlement that neither side would claim the invention. But 3M has violated that agreement, he alleges.
He asked for a trial but the judge favored mediation and gave the two parties until the end of the year to settle their differences.
3M was not immediately available to comment on Amron's lawsuit.
3M is one of the 30 blue-chip members of the Dow Jones Industrial Average and had $30.3 billion in sales worldwide in 2015. In addition to its consumer unit, which includes the Post-it notes, Scotch tape and Ace bandages, the company has a range of businesses from industrial and health care to electronics and energy.