One case involves the self-proclaimed market leader, Match.com, whose website claims to be "the world's largest online dating, relationships, singles and personals service", responsible for having inspired "twice as many marriages as any other site".
It has been accused in a Los Angeles lawsuit of sending false e-mails to clients, and using its own staff for meetings to keep them interested - a practice known as "date bait". Match.com denies the allegations.
The other involves the giant internet search engine Yahoo. Its personals service, according to another lawsuit in San Jose, California, has committed breach of contract, fraud and unfair trade practices. Specifically, it is accused of posting fake client profiles on its website to convince clients that it has more subscribers than it really has. Yahoo has made no comment.
Online dating services have a turnover of $250m (£149m) annually in the US. About 15 million people are said to have sought happiness through Match.com, paying $30 (£17.50) a month.
If the charges are to be believed, the buyer should beware. Match.com is alleged secretly to employ people to send in alluring profiles, and go on up to 100 dates a month - "date bait" to keep punters happy. "Hiding behind Match.com's portrait of online success is a very big, very dirty secret," says the Los Angeles lawsuit. "Not everyone you date through Match.com is just another Match.com member." Though brought by just one person, the case could evolve into a class action suit. The agency is promising a "vigorous" defence, saying it "absolutely does not" employ people to entice customers, and said the charges were "completely without merit". A spokeswoman pointed to a survey showing that 12 per cent of marriages last year resulted from online meetings as proof that such services were on the level. Match.com membership meanwhile, had risen by 19 per cent in a year.
But the lawsuit claims that employees keep track of customers whose subscriptions are close to expiry by secretly reading their e-mails. They then "make themselves appear to be the 'perfect match' to that person".
In a separate case, the New York-based Great Expectations dating service was ordered by a judge to refund money to two women who said they never got any dates after paying up to $1,000 (£580) for a six-month subscription. "I think I'll stick to meeting people at bus stops and the elevator," said one.Reuse content