This is a trademark issue, and when it comes to trademarks, brand logos, and anything having to do with use, whatsoever, the rules are much different, the measure of laxity much slighter, and the breadth of penalties/damages much broader than that of copyright alone. You should not change, alter, or build upon a company's trademarked logo without their explicit permission, and unless you're a big player with a huge internet presence, that permission is not likely forthcoming. How risky is it not to follow their explicit guidelines for use with their trademarked brand? Very risky indeed. Facebook has more money than most small nations, and like most multi-national companies with a recognizable brand, they have researchers that do nothing but search for violations, and attorneys who do nothing but protect their branding and enforce their trademark and copyrights. Brand resources are one of their most valuable assets. You should not endeavor to do anything they have not given you explicit (written) permission to do. If you are seeing different artistic renderings – especially on sites like IMDb, that are very popular, and attract a ton of traffic – it is much more likely than not that they sought permission to use that rendering. In fact, they may have rights to the artistic rendering, as licensed by and through Facebook, that makes that specific rendering theirs, alone, to use on their site alone, for the express purpose of directing their users to their Facebook presence.
Facebook has a do's and don't FAQ page about their brand resources, and below is a sample. This portion does not even include (but the link I will attach does), allowable use of other Facebook brand resources, such as their like button or their "find us on" logo. They even dictate how you are allowed to use their name (fonts, capitalizations, etc.,) when talking about them, or using their name or likeness in film or photography (including screen shots). All of this info can be found on their site, navigating from this link:
Other big brands (and even small ones) have the same or similar rules, which you can usually find on their homepage. If not, assume these same type general rules apply or seek specific advice about particular brand resource guidelines from the company/corporation itself.
Here is a sample
Only use the ‘f’ logo to refer to:
- Your presence on Facebook, such as your Page, timeline, group, app or event
- Your implementation of Facebook on your website
- Your product’s integration with Facebook, such as ‘For use with Facebook’
Content that originates from Facebook;
Include a clear call to action that communicates your use of Facebook (for example, ‘Like us on Facebook’ or ‘Install our app on Facebook’), unless the ‘f’ logo is side-by-side with other social media logos;
Use the version of the logo that comes with a blue box on white or light colored backgrounds;
Use the version of the logo that comes on a white box on blue or dark colored backgrounds;
Link directly to your presence on Facebook.
Don't: Modify the ‘f’ logo in any way, such as by changing the design or color.