Best Mode Requirement: If you know something special about best way to make invention, you have to tell us this. Okay if you are wrong, merely must say what you think.
a.    Why?
(A)    Avoids people using patent and trade secret system on same invention.
(B)    Want to stop people from writing patent listing hundreds of embodiments, hide the ball.
b.    How?
(A)    Objective component: Must be clear what sentence does this, can’t sneak it in.
(B)    Balancing: If best mode is totally economically infeasible, you have to balance the factors and give what you think to be, so if you think cheaper less effective way is best, you have to give it.
c.    Lax req: As of date of filing, if you file today and you improve claims over next few months and discover better mode, don’t have to update. One-time req. Might say best mode changes so quickly that BM is useless.
d.    Most BM cases involve filing party starts to make product. Other party can take what they produced and compare that against patent. Try to argue minor differences are significant. Otherwise trying to read inventor’s mind.