Intuitive Surgical has rallied more than $20 in the last five sessions since we cited unusual buying of stock and options in the company.
The sharp rise has taken place amid persistant takeover rumors involving Johnson & Johnson and the robotic surgery giant, which last month reported fourth-quarter results that were squeezed by strained hospital budgets.
A number of hedge funds have passed along the JNJ-for-ISRG buyout talk again today, but such rumor-driven rallies can end as abruptly as they start.
- More Options Tips from Jon Najarian
- Read The CNBC Stock Blog
Just over a week ago, we cited the options activity in Intuitive Surgical after its shares hit their lowest level since October 2005, trading to $87.14, but then investors seemed to recover their mojo and focused on the fact that even in such difficult times ISRG's net income grew 3.3 percent.
Its shares are up another 5 percent in midday Tuesday trading to about $108, but they were above $300 as recently as last August.
I have positions in ISRG.
More Medical Device Makers:
Jon 'DRJ' Najarian is a professional investor, CNBC contributor, and cofounder of OptionMonster.com.