According to a DMCA complaint documented on ChillingEffects.org (https://www.chillingeffects.org/notices/11039982#) and reported on at CNET (http://www.cnet.com/news/videos-taken-down-from-vimeo-for-using-the-word-pixels/), the video hosting site Vimeo has removed several videos from their service just because the videos used the word "Pixels" in the title. This is based on a complaint from the production company for the film "Pixels", a poorly rated Adam Sandler movie. (17% splat on RottenTomatoes.com, http://www.rottentomatoes.com/m/pixels/)
The videos removed included the short video that the film Pixels was based on along with several other videos that were posted on Vimeo years before the Pixels movie. It appears to me that the owners of these videos have a legitimate prior claim to the video title use of the word Pixels and could take legal action if they chose to. At the very least the removal of their videos from Vimeo is without merit and the videos should be returned to the site.
This action shows one of the problems with online video sites and unfortunately YouTube is not blameless in this regard. Video sites will usually honor DMCA copyright complaints without looking into the matter and will remove videos and even delete accounts without any attempt at verifying the legitimacy of the complaint. In the Pixels complaint it is patently obvious that videos uploaded years before the film Pixels was made clearly don't infringe on the film's rights. If anything the film Pixels is infringing on the other videos use of the word Pixels.
When the Batman film franchise was first rebooted with Michael Keaton playing Batman it is understandable that Warner Brothers would try to stop people from using Batman imagery and references to the 1960's TV show. First they owned the Batman name, image, etc. and secondly they were trying to change the look and direction of the product. This included forcing a bar near here to change its name from Gotham City and banning Adam West and Burt Ward from wearing any part of their costumes from the 60's TV show at fan conventions. (I got this last part first hand as I was working for Burt Ward at the time on a TV pilot project he was doing).
But in the Pixels case the word is simply the plural form of a public domain common usage word and has been in use since the mid 1960's. (http://dictionary.reference.com/browse/pixel). The only infringement here would be for uses of the word pixels that were trying to create a false impression of a link to or association with the movie Pixels. As far as I can see none of the videos removed by Vimeo fit this case.
All I can say is I hope that the owners of the videos that have been removed fight this action by Vimeo. As for the rest of us, I guess copyright infringement really means the company with the most money, the biggest name, and the best lawyers own the copyright. Doesn't matter whether or not it will hold up in court. YouTube is better about allowing Fair Use of content on their site, but if a company files a DCMA complaint with YouTube their first action is also to simply remove the video without researching the claim fully.
Here are some prior films with the use of the word Pixels in the title:
Pixels and Static (2009) - available on Amazon Prime
Legion: From Pixels to Picture (2010) - available on Amazon Prime
Looks to me like the makers of both of these films can go after the makers of Pixels for copyright infringement.
All of the above of course are only my opinions on the matter and I have written extensively in the past on video related forums about why you should never use copyrighted material in your videos unless you own the copyright or have received written permission. But actions like the above I consider attempts to steal copyrights from legitimate holders or users, or in this case an attempt to create a copyright or trademark half a century after the word entered common usage.
Unfortunately as shown above, even using common use words in our titles can sometimes get our videos removed from video sites.