Innershield is definitely a Lincoln trademark, but my understanding from the very limited search results was that the Lincoln trademark didn't come into play until a few years after Arthur Bernard called it Dualshield.  Lincoln expanded on it and developed a FCAW wire that didn't require external shielding.   

The following was taken from an article in October 2007 edition of The American Welder , “A Brief History of Filler Metals”

"With the introduction of welding with CO2 shielding gas came other filler metal inventions, notably the precursors to today’s flux cored wire.  Attributed to Arthur Bernard in 1954, who dubbed the process Dualshield®, flux cored arc welding (FCAW) began with the creation of a flux cored wire, similar to those manufactured today.  The flux itself generated shielding gas, but an external supply of CO2 was still necessary to protect the weld pool.  The development of a self shielded welding wire in 1959 would eliminate the need for an external shielding gas supply, and it was therefore called Innershield®"

Here's a link to that article........

http://files.aws.org/wj/2007/10/wj200710/wj1007-113.pdf

www.weldguru.com/welding-history.html
I haven't check this out but it might help.

   M.G.

I really think history is irrelevent for a beginning welding student or an engineering student.

Cored SMAW  Vs.   FCAW?   For one thing.....    Constant current vs Constant voltage power supplies.... The differences between a CC and a CV arc make it truely a apples and oranges conversation..

Now, while apples and oranges are grown in different parts of the garden, those differences are very much worth talking about.

FCAW/MCAW gains their greatest advantage via their particular way of producing a beneficial "current density" at the welding arc.

A student learner who wants to actually become an effective professional rather than please a misguided teacher, would learn the benefits and contrast the differences between a CV GMAW welding arc and a CV FCAW/MCAW welding arc as they relate to the following:

1,  Fillet weld penetration profile and how this may effect design engineering of weld sizes in steel joinits.

2,  Deposition rates of MCAW/FCAW  vs  GMAW with solid wire in manual and automated sceneros.

Understand the process factors that answer questions 1 and 2 and you are well on your way to being a welder who can make money by a means other than just pulling the trigger with a steady hand... You take your first steps toward becomming a weld decision maker.