Less than a week after the launch of the iPhone 4, both the device's maker, Apple, and its exclusive network carrier in the United States, AT&T, are facing multiple class action lawsuits accusing the companies of knowingly selling faulty products.

Since Tuesday, at least four separate suits focused primarily on the poor connection resulting from the phone's antenna design have been brought against the companies. The various counts the plaintiffs have charged Apple and AT&T with include negligence and intentional misrepresentation, claiming that Apple had knowledge of the antenna's defects before the phone's release.

According to a public statement made by Kershaw, Cutter, and Ratinoff (KCR), one of multiple law firms involved, more than 1, 500 iPhone 4 owners experiencing poor reception quality had contacted the firm since it first released an inquiry investigating the issue on Monday, June 28. The Sacramento-based law firm filed an official complaint on Tuesday in the Northern District of California.

The suits hope to seek some kind of retribution for iPhone 4 customers, whom the class action lawyers argue have not been given a fair level of customer support.

According to the suit filed by KCR, "consumers are left with three options: hold their phones in an awkward and unnatural manner; return their phones and pay 10 per cent 'restocking fee', or purchase Apple's own 'bumper' cases for their phones, costing 29.95 U.S. dollars in addition to the premium they have already paid for the phones themselves, which may somewhat ameliorate the iPhone 4's defects."

As part of the iPhone 4's new design, a wraparound metal antenna intended to give the phone a slimmer look and better reception has instead become one of its largest drawbacks. Even prior to the phone's public release last week, complaints had surfaced in online forums from those who had preordered the device that holding the phone in certain ways resulted in noticeably reduced connectivity and abnormal levels of dropped calls.

Unlike most smartphones in the market today where antennas are located in the bottom of the phone, the iPhone 4 has two antennas running along the phone's exterior, one for its Bluetooth and Wi- Fi capabilities and the other for cellular reception. When a user' s grip touches the point where the two antennas meet, a significant reduction in reception may result.

The issue is especially common among left-handed users since contact with the intersection between the two antennas, located in the bottom left hand corner of the phone, is more likely.

Apple, however, has attributed this as a software glitch rather than a flawed design in its hardware. In a public letter issued Friday morning, Apple said that the dramatic drop in signal coverage strength was due to a formula calculation error.

"For example, we sometimes display 4 bars when we should be displaying as few as 2 bars. Users observing a drop of several bars when they grip their iPhone in a certain way are most likely in an area with very weak signal strength, but they don't know it because we are erroneously displaying 4 or 5 bars. Their big drop in bars is because their high bars were never real in the first place," said the company in the letter.

Apple said it will release a new software patch within a few weeks to address the issue, which it stated has also been an undetected issue among the iPhone 4's predecessors, the iPhone 3GS and iPhone 3G.

JR Parker, one of four attorneys at KCR on the case, said that this does not resolve the core issue addressed in the lawsuits.

"Essentially they're still saying that you're holding the phone wrong...they're going to change the display but that does not solve the problem that you still can't touch the black band in the lower left hand corner," Parker told Xinhua in a telephone interview.

This is not the first time that the tech company has faced legal woes from spotty reception on its phones. When Apple's iPhone 3G first launched in 2008, a total of 12 lawsuits were brought against the company on the grounds the phones did not live up to the performance levels advertised and consistently dropped calls.

Despite these challenges, neither AT&T nor Apple has seen significant declines in the popularity of the device. With over 1. 7 million handsets sold within the first three days, Apple's CEO, Steve Jobs, called the iPhone 4 Apple's most successful product launch to date.

Apple's shares opened Friday morning at 250.70 dollars, down from its previous opening share price of 254.30 dollars.