"Like Facebook, only better" - Can I legally use this in advertising for my website. Is it possible to do so without getting sued?
UK-based answer here:
It is entirely legal for a firm to make a statement which compares itself to a competitor, so long as it is true (Defamation Act 2013 s2) or is an honest statement of opinion (Defamation Act 2013 s3(1)).
However with regards to a "statement of opinion", generally speaking a disclaimer of "it is our opinion that..." is necessary because certain statements may be ambiguous as to whether they are opinions or not.
For example, "I hate x, he sucks," is a clear statement of opinion but "X is ugly," may or may not be one, whereas "I believe that / It is my opinion that X is ugly," reaffirms that this is an opinion. I use the example of someone calling someone else ugly because in Berkoff v Burchill (1996) All ER we know that calling someone ugly counts as defamation if their career can be impacted by it (in this case the complainant was involved in showbusiness and was called "hideously ugly").
But do note that with regards to statements of opinions, a basis for this opinion must be indicated in the statement (Defamation Act 2013 s3(3)).
The law on defamation (while mostly case law, see Defamation Act 2013) is that a statement has caused or is likely to cause serious financial or reputational harm to a person (or firm) (see DA 2013 s1).
In a commercial context this means a business can commit defamation if they say something that is not only false but also causes serious financial harm to the victim of the false statement.
Because of this, firms will not often directly attack or compare themselves to other large competitors, unless these are factual comparisons (e.g., "Our apples are 50% cheaper than Tesco's/Walmart's apples!").
The problem with the statement "like Facebook but better" is that it is hard to outright prove that your site is better in every way than Facebook, or is overall a better experience. However if this statement was scrutinized in court one would argue that it was simply an obvious statement of opinion rather than fact (an obvious statement of opinion is a defence to defamation).
That all said, DA 2013 s1(2) requires that:
For the purposes of this section, harm to the reputation of a body that trades for profit is not “serious harm” unless it has caused or is likely to cause the body serious financial loss.
So if a small social networking site makes such a statement, Facebook would need to show that they have suffered massive financial loss as a result of the statement, or would likely suffer serious financial loss in the future.
So I would argue that the statement "like Facebook, only better" is a realistically safe statement to make (unless the site becomes so successful it takes a majority of Facebook's users away, in which case the site would likely get sued and may have to take the statement down).