THE Bikini Beach Hotel in Panama City Beach, Florida, serves sunbathers of all types. So John Gheesling, the owner, was surprised to be sued for violating the Americans with Disabilities Act (ADA). Apparently a visitor last August found the pool lacked a wheelchair lift, though the hotel keeps one available inside. “Never had anyone ask to use it,” Mr Gheesling says. But fighting such lawsuits is tricky. He has already spent $8,000 in legal fees and there is no end in sight. As it happens, the same plaintiff sued nearly 50 other businesses along the state’s Panhandle in the same month, and filed 529 ADA suits in Florida in 2014.

Signed into law in 1990, the ADA bars firms from discriminating against people with disabilities, whether they are employees or customers. Banks, shops, hotels and other “public accommodations” must remove barriers to the “full and equal enjoyment” of their goods and services. This guarantee may sound vague, but new technical standards from the Department of Justice, which went into effect in 2012, dictate everything from the slope of a ramp to the height of a bathroom basin. The regulations are well-meaning but confusing. The government enforces some of them, but mostly leaves it to people with disabilities to sue. Plaintiffs need not be customers, an appeals court decreed in 2013. And if they win, the defendant must pay their costs.

This has created a cottage industry of so-called Title III lawsuits against bars, motels and the like. More than 4,430 reached federal courts in 2014—a 63% rise in one year, according to new data from Seyfarth Shaw LLP, a law firm that defends businesses against ADA claims. Many more cases rattle around state courts; most end in a confidential settlement. The lion’s share took place in California (where plaintiffs can sue for damages, too) and Florida (which has a high concentration both of lawyers and of frail elderly residents). The law’s new standards, which include requirements for pools, help to explain some of this rise. More lawsuits may soon be on the way, as the Justice Department is expected to apply new ADA rules to websites in June. For example, each picture must have text describing it, so that screen-reader programmes can tell blind people what is there.

Some customers have legitimate claims. But most lawsuits involve a minor technicality, such as the height of a soap-dispenser or the width of a parking spot, which has little bearing on the accessibility of a business, says Martin Orlick, a property lawyer in San Francisco who specialises in ADA compliance. Because fighting in court can cost $30,000-60,000, businesses often prefer to pay a smaller sum to make a lawsuit go away.

There is evidence that lawyers explicitly target small businesses, which are more likely to pay up without a fight. In a tour of over 1,500 firms that had been hit with lawsuits in central California, Julie Griffiths of Citizens Against Lawsuit Abuse, an advocacy group, found mostly immigrant-owned family businesses earning between $50,000 and $80,000 a year. Settlements usually run to around $10,000 before anything is fixed. “I know guys who are on payment plans with some of these lawyers,” Ms Griffiths says.

Some argue that lawsuits are the only way to ensure that businesses accommodate disabled people. Kevin Berry, an ADA-compliance advocate in south-west Florida, is not so sure. He finds that lawyers working with serial plaintiffs will file a bundle of “drive-by” lawsuits at once, slamming businesses with vaguely-worded grievances that leave many wondering what they have done wrong. Instead of explaining the problems, these lawyers often turn around and suggest a settlement. “They’re in it for a quick buck,” he says.

Few companies manage to follow all the rules, which are 252 pages long and very precise. But if there is a real problem Mr Berry, who uses a wheelchair, says he finds it easy to ask businesses to make changes. Most oblige. A customer is a customer. Nearly a fifth of Americans have some kind of disability, and they have an annual discretionary income of $200 billion. As spendthrift baby-boomers enter their golden years, these numbers are expected to rise.