U.S. Patent Nos. 6,007,209 and 6,473,554 are directed to uniform backlighting LED panels (pages 2-3). “Emitted by plural lights sources mounted on said internal bottom wall” is required by claim 20 of the ‘209 patent (page 9). The prior art does not mount light sources on the bottom (page 9). A witness suggested modification to mount on the bottom is not enough to show anticipation (page 9). For the ‘554 patent, “illumination coupler” has a top and bottom surface to direct light together, so that an encapsulated LED of the prior art does not provide a bottom surface (pages 10-11). The LED is positioned in a middle, not “beneath a central portion” (page 11). The light of the prior art is distributed to the right and left, not leaking from a top surface (page 11). The anticipation portion of the decision turned on witness support and believability (pages 9-12).
Hindsight: Be cautious when including limitations directed to position. Use of relative locations or result of positioning rather than absolute position may allow for a broader claim, which may increase likelihood of invalidity.