At 42, the managing partner of Saidman, Sterne, Kessler & Goldstein wears a nicely tailored suit and a silk tie, looking pretty much like the $250 an hour lawyer that he is. But Perry J. Saidman's fancy Connecticut Avenue office, where he sits surrounded by his clients' wares, looks rather like the back room at a shoe store.

He walks the six blocks from home to work in Avia sneakers. And when asked, he can rattle off the model number (360). Even without prompting, he talks with as much enthusiasm for -- and probably more knowledge of -- the sneakers than a salesman.

After all, Saidman is using design patents to give athletic shoemakers a potent weapon in their arsenal against producers of counterfeits.

"You can't be afraid of technology. These shoes are engineered. Blueprints are made," he said. Saidman holds a pair of Avia shoes, bending the concave sole and explaining the patented cantilever design. The sole provides a spring-like action that cushions the foot and provides stability, he said.

"Even though it's just a shoe, and everybody understands a shoe, there's an awful lot of technology involved," he said.

Saidman recently convinced a federal judge in California that a shoe sold by LA Gear Inc. looked too much like a shoe developed by his client, Avia Group International Inc. Patent experts said this is the first time a court has enforced a design patent claim by a footwear maker.

"If there is such a thing as state-of-the-art lawyers, I think Perry's on the leading edge," said Avia Vice President Bruce W. MacGregor from headquarters in Portland, Ore. Avia is a unit of Reebok International.

Even the losing side praised Saidman's handling of the case. "They were a hell of a lot sharper than my attorneys," said Elliot J. Horowitz, executive vice president of LA Gear. The Los Angeles shoemaker plans to appeal the case.

A judge will determine how much profit LA Gear made off the shoes in question. That figure will be doubled or tripled because the federal court ruling cited "willful infringement" by LA Gear after evidence showed Avia had notified the company of pending patents on the shoe's design. Avia also will recover legal fees, which are now about $100,000. LA Gear spent about half that amount, Neither side had estimated LA Gear's profits on their version of the shoe at more than $112,000, so why did Avia pursue the litigation so vigorously?

"The culture in the footware industry is it's okay to do this, it's okay to copy the popular styles," Saidman said. "We wanted to make it very clear to LA Gear that it would be very expensive for them to do this in the future. We wanted to teach them a lesson, that they should not knock off {copy} Avia designs."

LA Gear officials defended the widespread copying of footwear, and said they did not know the sneaker they bought from a Korean supplier infringed Avia's design. "Everybody does it. How many penny loafers have you seen? Everybody in the world makes them," Horowitz said. "That's all anybody in the shoe industry does is copy everybody else and make a couple changes."

Pirating is endemic in a range of consumer and industrial goods including designer jeans and handbags, recordings, agrichemicals, pharmaceuticals, computers and spare parts for automobiles. Legitimate U.S. business loses between $8 billion and $20 billion a year to look alikes, according to estimates by the federal International Trade Commission.

One Commerce Department official said U.S. losses could be worse. "Customs has done a superb job making sure that the domestic market has not been flooded by these goods," said James P. Moore Jr., deputy assistant secretary for international economic policy. But the problem "continues to rage out of control."

"In the knock-off industry, these manufacturers may not be first in fashion, but they brag about being a quick second," Saidman said, shaking his head. Knock-off products use designs or processes owned by one manufacturer, bearing the label of another. Counterfeits are fake brand-name goods.

Both are big business in the Far East and in the developing nations. The most commonly cited offenders are South Korea, Taiwan, Singapore and Indonesia. U.S. government and industry representatives have been negotiating with these and other governments to improve protection for copyrights, trademarks and patents, with some positive results. In South Korea, laws affording foreign companies more protection went into effect July 1.

"It now is important for the U.S. to be watching these countries very closely to make certain they are living by the agreements. We're talking about countries that haven't had intellectual property laws for their entire histories," Moore said.

The pressures to steal established goods and popular styles are great. "Pirating is turned to as a means to get into the mainstream of world commerce. It generates income and revenue for these countries," said Michael K. Kirk, assistant commissioner at the Patent and Trademark Office. It also provides a shortcut to industrialization.

"If U.S. companies cannot safely invest in research and development and get patents and copyrights to protect the U.S. market, they are going to be less likely to develop new products, hi-tech products, in the future," said Herb C. Wamsley, executive director of Intellectual Property Owners Inc., an association of manufacturing companies.

Manufacturers are hard pressed to find effective countermeasures. "I don't know how you stamp it out. It's like the 55 mph speed limit. People turn their heads," Saidman said. The strategy he uses is aimed at convincing pirates to look elsewhere, to make his clients' products too costly to copy in the long run.

Avia officials see their victory over LA Gear as pivotal. "If we would have lost this suit the ramifications would have been horrendous for the entire industry. It would have legitimized the companies that make a living off copying brand names. It would have turned the whole thing into a free-for-all," MacGregor said.

In court papers, Avia said LA Gear's "Boy's Thrasher" was a knock-off of its Model 750, introduced in 1985 and described by company officials as Avia's first and most popular man's tennis shoe. ("You're not going to find cute little names on Avia shoes. They view themselves as a very hi-tech shoe," Saidman said.) The 750 retails for about $50. Avia sold 42,000 pairs in 1985 and about 250,000 last year. The LA Gear boy's version, which sold in high-top and low-top models, was priced under $40 -- and often much less. Like many knock-offs, the "Boy's Thrasher" was sold in discount stores and chains.

Saidman digs through his shelves and pulls out a knock-off shoe, holds it next to an Avia. "When people see a product like this they wonder if Avia suddenly started putting out," he hesitates, " ... junk." And that hurts business, he said.

Because design patents usually take so long to get and can be easily circumvented -- "one or two changes is all it takes," said LA Gear's Horowitz -- they have not been widely used. About one design patent is issued for every 15 utility patents. Design patents cover the ornamental aspects of an article, rather than the article's structure or function. Such items as shoe soles or uppers, which are ornamental and functional, have been difficult to protect. A bill to create a copyright-like protection for industrial designs has passed the Senate several times in the past 20 years but has never been enacted.

In footwear and fashion, items go out of style faster than patents get granted.

Michael W. Blommer, executive director of the American Intellectual Property Law Association, said, "In the area of designs, sometimes the market's passed you by by the time the patent issues. Manufacturers like Reebok, they're constantly changing the style of their shoes. They're going to start selling their shoes while the patent is pending. The knock-off artists are in and out of the market in a year or two."

Saidman is reluctant to reveal his methods for fear of losing his clients' edge, but readily proclaims that he cut the process of obtaining a design patent from the average of two and a half years to nine months.

"That's pretty fast," said Wamsley. "It's got to be one of the few cases in recent years where anybody has been able to get any kind of effective relief under the design patent law."

The "special status" provision is a "little known, little used" technique involving extra work and extra cost for the would-be patentee, according to Kenneth I. Cage, director of designs at the Patent and Trademark Office. Applicants who do the pre-examination research or who can demonstrate that another manufacturer is infringing their idea can receive special status.

But the extra work amounts to about $1,000 per patent, Saidman said. "It's nothing, it's insignificant compared to the amount of money at stake, and the amount of power a design patent has in the marketplace, as evidenced by this case."

Saidman didn't always deal with sneakers, although his primary clients are Avia, Reebok, Rockport, Frye and Donner Mountain. He has a masters degree in electrical engineering from the University of Pennsylvania. And much of his early patent practice involved electronics.

Saidman, Sterne, Kessler & Goldstein represents a number of large manufacturers and universities, and their practice extends to the more high-tech areas of artificial intelligence and biotechnology.

While a scientific background is not essential for a patent lawyer, it helps, according to Saidman. "We are the communicators. We are the ones who explain the technology to the judges and juries of the world," he said.