Here is a page talks about Entities
A document must use escaped entities for Less than (<), Greater than (>), and Ampersand (&). In addition, within HREF or IMG elements, a document must use escaped entities for equal sign (=), quote ("), and space ( ). A document need not use escaped entities for any other characters coded 126 or below. A document need not use escaped entities for characters coded 128 through 255, provided that the codes are in conformance with ISO 8859-1 ("Latin-1"); however, use of the escaped entities is recommended in this case.
So I'm not 100% sure so you would have to test this tradtips, but your code with changing the equal sign into an entity
see if this works
& # 61 ; (without spaces) (=) Equals sign
so swap the equals out for the entity code
see if that tests on the w3 validator.
all I did was where there is an equal sign =, I substituted the entity code =
course I'm not 100% certain when it comes to w3 and the entity codes and different standards.
Edit: I had to make a text file since putting the entity code in a post to show doesn't work, doesn't even show inside code format.
Anyhow I changed your equal signs to entities and posted it in a text file for you to actually see what I did
I swapped the equal with the entity code for equal. That should work on the validator