U.S. homebuilder Lennar Corp. responded to an accusation from the Fraud Discovery Institute Inc. lead by Barry Minkow calling him a convicted felon and saying his claims are false.

The FDI released a 30-page report, a YouTube video and a website (www.lenn-ron.com) charging that Lennar was making joint ventures like a Ponzi scheme.

Today convicted felon Barry Minkow, acting as an agent for a disgruntled litigant, Nicolas Marsch III, posted false and inflammatory accusations concerning Lennar, the company said stating Marsch's civil litigation against Lennar was just dismissed by a California Superior Court judge.

This Internet posting was hurriedly made only after evidence surfaced this week in litigation that Marsch and Minkow may have attempted to illegally obtain information relating to Marsch's legal proceedings against Lennar, the company added on a press release.

Lennar says it continues to investigate acts of wrongdoing by Marsch and Minkow.

Earlier, shares of Lennar dropped as much as 28 percent in New York trading after Minkow's accusations.

Minkow has previously served seven years in prison for stock fraud.