Fremont, Calif. - Barnes & Noble's much lauded e-reader, the Nook, is not yet available, but it is already the subject of a lawsuit, filed Nov. 2 by Spring Design.

Spring Designs says the Barnes & Noble Nook (left ) violates the intellectual property used in its Alex (right).

Spring Design plans a similar e-reader called Alex, to be officially unveiled at International CES.

Spring Design filed a complaint with the U.S. District Court for Northern California in San Francisco, citing a violation of intellectual property rights.

Eric Kmiec, Spring Design sales and marketing VP, said Spring Design showed Barnes & Noble its Alex with the intention of collaborating on an e-reader, and was surprised to learn that the bookseller had developed a similar e-reader without notifying Spring Design.

"Our goal is to develop a strategic relationship with them ... We've been working with them for a couple of years.  The way to resolve this is working together to develop this market."

Spring Design said it applied for a patent on its dual-screen design that dynamically links an e-reader screen with a smaller color LCD screen back in 2006 and that it is in the final stages of winning patent approval.   The Barnes & Noble Nook has a similar design; both run on Google's Android platform, and they offer 3G and Wi-Fi wireless connectivity.

Spring Design expects to partner with publishers and bookstores to sell the Alex and expects to announce at least one such collaboration at CES.