Lawsuits over an allegedly faulty hip implant are piling up for DePuy Orthopaedics, with three more patients suing the Johnson & Johnson (NYSE:JNJ) subsidiary over its ASR acetabular cup.

Cynthia Magowan, Harold Schoening and Katherin Balestra-Walter each received the device, according to a lawsuit filed in the California Superior Court for San Francisco, and each had to have revision surgery after the cup partially detached from their hip sockets.

The trio accuse DePuy of liability for manufacturing a defective product, failing to warn patients and doctors of problems with the implant and negligence in designing, manufacturing and selling the product.

It’s the latest of what’s likely to become an avalanche of liability lawsuits over the implant, after a Florida woman, Kathleen Margenau, sued on similar grounds earlier this month. Spencer Pahlke, a lawyer for the firm representing Magowan, Schoening and Balestra-Walter, told MassDevice that his firm, Walkup, Melodia, Kelly & Schoenberger, has several more suits in the works.

DePuy, which introduced the ASR in the U.S. in 2005 after winning 510(k) clearance from the Food & Drug Administration, allegedly knew of design problems with the cup but failed to adequately warn physicians, according to the lawsuits.

"During this time, defendant DePuy was aware of a high rate of failures of its ASR cups, but did not provide this information to [Margenau’s surgeon]," according to Margenau’s lawsuit. "As a result of defendant DePuy failing to provide this crucial information to plaintiff’s orthopedic surgeon, [he] had little reason to suspect that the source of plaintiff’s ongoing pain and weakness was the result of the failure of the ASR cup."

Magowan, Schoening and Balestra-Walter make similar claims in their lawsuit, according to court documents.

DePuy discontinued the cup and had phased it out by March of this year, sending a letter to doctors that month warning that data from the Australian medical device registry showed a "higher-than-expected" failure rate in traditional hip replacements, especially in smaller patients or those with weak bones.

Those moves followed two years of reports that the implant was prone to early failure, according to the New York Times. Dr. Stephen Graves, the director of the Australian database, told the newspaper that the company was too slow in pulling the device from the market. The FDA received about 300 complaints about the ASR cup since 2008, according to the Times, with most complainants undergoing revision surgeries to replace the device. And the device’s co-developer, Dr. Thomas Schmalzried, said he and DePuy officials realized that the ASR cup might be more of a challenge to implant properly than competing cups.

“The window for component position that is consistent for good, long-term clinical function is smaller for the ASR,” than other cups, Schmalzried told the newspaper, which reported that he received $3.4 million from DePuy for his work on the ASR and other devices.

DePuy acceded that the device posed "a theoretical potential" to "be more sensitive to component position," but cited data from other studies and examinations of explanted devices that contradicted that finding. A DePuy spokeswoman said the company does not comment on pending legal matters.