Shares of medical device maker Cyberonics (CYBX) are recovering some of yesterday's losses in early trading after the company refuted allegations made by a short selling blog and the blog revealed it has already covered its short position. Cyberonics said yesterday's report from TheStreetSweeper contained information that has been in the public domain for years and doesn't "accurately characterize the benefit that VNS therapy provides patients and the opportunities for the company," according to The Wall Street Journal. TheStreetSweeper also raised questions about what it called a "whistleblower event," but Cyberonics said it is unaware of any qui tam, or whistleblower, lawsuit as described in the report, the WSJ said. Cyberonics added it can't comment on active litigation but intends to vigorously defend the lawsuit. On a posting to its website, TheStreetSweeper stated, "On Jan. 23, TheStreetSweeper covered its short position in CYBX at an average price of $44.63 a share and no longer holds a position in the stock at this time." Shares of Cyberonics, which fell 8.57% yesterday, are up $1.40, or 3.18%, to $45.38 in early trading today.