Investors, who sent shares of Intuitive Surgical (NSDQ:ISRG) down 10% the 1st time Citron Research issued a negative report on the medical device company, yawned today at a 3rd missive from the short seller.

ISRG shares were up slightly as of about 3:30 p.m. today to $561.07 apiece, despite Citron’s repeated assertion that the stock is headed for $300 per share.

Citing a study and accompanying editorial published yesterday in the Journal of the American Medical Assn. questioning whether robot-assisted hysterectomy using a device like Intuitive’s da Vinci surgical robot is worth its extra cost, the latest Citron broadside warns investors that the stock is significantly over-valued.

As with the 1st 2 reports, the latest also cites claims in personal injury lawsuits filed against Intuitive over the da Vinci robot. Last December the 1st Citron release pared 10% from ISRG’s share price. A 2nd, released last month ahead of Intuitive’s 4th-quarter earnings, initially pushed shares down but was superceded by a positive report from Goldman Sachs, whereupon shares rallied.

"This is not a story of shorts vs Intuitive Surgical , this is a story of the American Medical Assn., the Affordable Health Care Act, and tort law vs Intuitive Surgical," according to Citron’s latest warning.