St. Jude Medical filed a lawsuit last month against the investment firm and research agency that issued a report in August claiming their cardiac implants were vulnerable to hacking. St. Jude filed suit against Muddy Waters (an investment firm) and MedSec (a security consultant) after it was discovered that Muddy Waters was shorting St. Jude stock, and that they have a deal with MedSec to split the profits made by shorting. This information calls the report's truthfulness into question due to the fact that Muddy Waters and MedSec both have a strong financial incentive to make claims against St. Jude to cause the stock price to fall.
Most recently, Muddy Waters filed a third party research firm's report in court validating MedSec's initial report's findings. The report, by BishopFox, states that the initial report's findings are accurate. BishopFox also claims to have been able to repeat the cyber attacks on the devices that the initial report described.