Upon further review, it appears that the logo with the stylized "X" is not yet registered -- because the applicant has not disclaimed the term, "worldwide," which appears in the logo. Also, the logo is highly stylized, and not at all in the style that you have described. If you were to create a B&W logo that was a silhouette of the Plexis logo, then assuming that the logo is finally approved and registered, you would be liable for infringement. However, if you intend to set the X on its side, then that's quite different from the Plexis Worldwide trademark. Consequently, I do not believe that an ordinary consumer would be confused by your proposed logo -- at least not unless and until Plexis becomes a very famous mark. Example: Let's say we're back in the 1970s, and Apple Computer has just released its Apple One computer. The Apple logo is unknown, and in fact, no consuer knows what a personal computer is, yet. So, if you were to publish the term, "Apple" with an illustration of an apple lying on its side -- no one would confuse your logo with the Apple Computer logo. But, today, if you were to do the same thing, everyone would instantly understand what you were doing, and the question would be: are you engaged in parody/poking fun at Apple Corporation (which is fair use
and not infringement) -- or, are you trying to trade on the Apple logo, so that consumers are confused by your logo, so as to wrongly associate it with Apple Computer? In sum, I seriously doubt that Plexis could win a trademark infringement
action against you today. 10 years from now, if Plexis Worldwide becomes a billion dollar business -- that may be a very different story. I hope I've answered your question. Please let me know if you require further clarification. And, please provide a positive feedback rating for my answer -- otherwise, I receive nothing for my efforts in your behalf.Thanks again for using Justanswer!