Question: What is the difference between *to allege* and *to claim*? Can I use them interchangeably? Or perhaps I can only *allege* something illegal?

For example, from CNET:

> 
> Over the past several months, the two companies have been embroiled in
>  litigation in which Apple **alleges** that Samsung illegally copied
>  technology and design aspects of the iPad to create the Galaxy Tab.
> 
> 
> 

If I replace *alleges* with *claims*, does it change the meaning at all?

Answer: 
[*Alleges*](http://www.oxfordadvancedlearnersdictionary.com/dictionary/allege) means:

> 
> to state something as a fact but without giving proof
> 
> 
> 

It is very similar to *claims*, but it is used in situations where there is a legal accusation which has not yet been resolved. For example, Apple here *alleges* Samsung copied technology. This may or may not be true, but in any case it is a legal claim. 

You could use *claims*, but it wouldn't have the same connotations.
Allege is used when no evidence is available so it is not sure or accurate yet. It is a statement that is made without giving proof, accusing somebody of doing something that is wrong or illegal.

Claim is used when evidence is available and it is sure and true.

the two words are not the same and cannot be used interchangeably.