Raymond Niro Sr., a seminal figure in intellectual property law whose incensed opponents dubbed him the first "patent troll," died unexpectedly Monday while vacationing in Italy. He was 73.

Niro's skills as a negotiator and trial lawyer made him a hero to inventors and a painful thorn in the side of corporate America. A string of multimillion-dollar jury verdicts in the 1990s and the early 2000s landed him among the National Law Journal's top 10 trial lawyers in the country and inspired Intel Corp. to slap the "troll" moniker on him and a client in 2001. The label stuck but it didn't slow down Niro or the generation of patent attorneys who emulated his business model, at least not until the last few years.

"Ray is one of the individuals who's had the biggest impact on the intellectual property business in the last two decades," said Jaime Siegel of IP advisory firm Cerebral Assets, who squared off against Niro many times during an eight-year stint as a senior IP attorney at Sony Corp. of America. "Whether you loved him or hated him, you had to respect him because he served his clients well."

"American inventors have lost their greatest champion," said Dean Niro, his son and law partner, in a written statement.

To his critics, Niro popularized the model of non-practicing entities—people or companies that acquired patents purely for the purpose of asserting them. Facing such a suit from Niro and client TechSearch in 2001, Intel Corp. lashed out at them as "extortionists," prompting TechSearch owner Anthony Brown to sue for libel. Intel's assistant general counsel at the time, Peter Detkin, shifted to the less actionable "patent troll," going so far as to line his office with troll dolls to drive home the point.

"Troll" has since been enshrined in the legal lexicon, but for many years it didn't seem to put any dent in Niro's business. According to the IP Watchdog blog, Niro tried 6 percent of all the patent cases that went to verdict in 2006, recovering damages of more than $100 million.

The son of a bricklayer who grew up in Pittsburgh and went on to earn a degree in chemical engineering, Niro understood patents and possessed the charm and sense of humor to make them accessible to judges and juries. "The story in a patent case has to be a story of invention and of an inventor," Niro told Law360 earlier this year. "If you can get an inventor to tell his or her story, it's powerful."

Flachsbart & Greenspoon partner Robert Greenspoon, who practiced with Niro before starting his own law firm, said Niro had immense respect for the sacrifice made by jurors, and little patience for any "fumbling or bumbling" among trial team members that delayed proceedings for even a few seconds. That meant no looking through boxes or searching through papers when the jury was present. "It was an absolute mandate: 'No fumbling or bumbling,'" Greenspoon recalled.

For every big trial verdict there were many more licenses privately negotiated. Critics complained that Niro used the threat of expensive litigation to wring settlements out of vague patents. Those arguments aside, Siegel recalled Niro as a reasonable negotiator with good business smarts. "He's one of the best negotiators I ever went up against, and I went up against him many, many times," Siegel said.

Niro got into the patent enforcement business by chance. He had been a partner at a Chicago litigation boutique when in 1976 he and Gerald Hosier split off to start their own firm. An early client was the inventor of the automatic shut-off nozzle used on gas station pumps. The client couldn't afford hourly lawyer rates, and begged Niro and Hosier to take the case on a contingency fee basis. When they recovered $200,000 without going to trial, the lawyers were "ecstatic," Niro told The Recorder in 2001. "We got $50,000 each and all we did was file a complaint and take discovery."

From 1994 to 2001, Niro said, his firm won 20 multimillion-dollar jury verdicts in a row generating in excess of $400 million. His fee generally ranged from 35 percent to 45 percent of the gross revenues.

A personal coup came in 2008 after Niro got into a war of words with the then-anonymous blogger behind Patent Troll Tracker, a website critical of Niro and his business model. Niro offered a $15,000 bounty to anyone who could reveal the blogger's identity. Richard Frenkel, then of Cisco Systems, now of Latham & Watkins, subsequently unmasked himself after a reader threatened to identify him. According to Niro, nobody claimed the bounty.

Lawyers who've worked alongside Niro described him as genuinely passionate about his work. Following heart surgery about a decade ago, Niro announced to the firm that he would be stepping back from active practice while continuing to be available as a mentor to younger attorneys. "That lasted for about five minutes," Greenspoon quips. "At that point we all knew he wasn't going to retire."

The patent assertion business has landed on tougher times the last few years with the passage of the America Invents Act, Supreme Court decisions on patent eligibility and fee shifting, and appellate court decisions reining in patent damages.

Niro's firm frequently found itself in the crosshairs. When President Barack Obama called for a crackdown on patent assertion entities in 2013, he singled out one—Innovatio IP Ventures—that was represented by Niro, Haller & Niro. Niro and Anthony Brown, his client from the TechSearch days, tried bringing an antitrust suit against RPX Corp., accusing the defensive patent aggregrator of unfairly driving down the value of patents. They lost the suit.

In the last two years, Niro Haller and its clients were hit several times with fee-shifting judgments, including one last year in which Niro, three other lawyers and the firm were held jointly and severally liable for $4 million.

Niro Haller disbanded around the first of the year and reconstituted as Niro Law. It numbers 13 attorneys, fewer than half of Niro Haller in 2014.

Niro made no bones about the difficult environment facing patent owners in recent years. "The American patent system is supposed to protect the American inventor," he told Law360 earlier this year. "It doesn't do that anymore. It protects Google; it protects Apple; it protects Cisco. But it doesn't protect the American inventor."

"The people that wanted to destroy individual inventors and their ability to pursue claims have won," he added.

Despite the challenges Niro had not shown signs of slowing down personally. His vacation to Italy reportedly included both swimming and consulting on client matters.

Davis Wright Tremaine partner Martin Fineman, who teamed up with Niro on a big IP case in San Jose a few years ago, said Niro brought along a whole generation of IP lawyers while reshaping the profession. "He's one of the people who really made patent litigation what it is today," Fineman said. "I don't know that it would be the major branch of the law that is now without him."

Scott Graham can be reached at [email protected]. On Twitter: @ScottKGraham