how to judge if anyone infringes my invention?

Question

My invention has A, B, C and D components and they are connected with each other with that order.

Somebody claims to have a new invention with an addition component Z with my invention:

Case 1:

If the Z component is added between A and B, does his new invention, A, Z, B, C and D, infringe my invention?

Case 1b:

For the Case 1, if Z improves (better results, easier for B,C,D components) the invention a lot, does this new invention infringe my invention?

Case 1c:

For the Case 1, if Z doesn't improve the invention a lot, does this new invention infringe my invention?

Case 2:

If the Z component is added before A or after D, does his new invention infringe my invention?

Answer 1

Infringement differs case by case, infringement of your invention depends on what are the claims you have been granted for your invention.

Eg: If your patent claim granted was "an invention comprising A, B, C and D components and they are connected with each other with that order" and addition of new component Z would infringe your be considered as an infringement. It is accepted by courts that term comprising is an open ended term and addition of unclaimed element would account to infringement.

If your claim granted was "an invention consisting A, B, C and D components and they are connected with each other with that order" and addition of new component Z would not be considered as an infringement. It is accepted by courts that term consisting is an closed ended term addition of new element or removal of an element would-not be considered as an infringement.

The above said example is a broad generalization how infringement would be evaluated and it differs from country to country.

In US courts the infringement of a claim would be evaluated after Markman hearing
during which federal judge construes the claim and the compare it against the invention of accused.

In the above hypothetical infringement cases there are numerous factors which play role which could potentially influence the infringement Viz., doctrine of equivalents, claims surrendered during prosecution, alternatives that existed during the priority date.

I would suggest you to consult an attorney as they would be in a better position to evaluate infringement.

Answer 2

I am not a lawyer, but here is my opinion.

Case 1:

If the Z component is added between A and B, does his new invention, A, Z, B, C and D, infringe my invention?

Yes a product with Z added to your patent's claim of A, B, C and D would infringe on your patent since it implements all aspect of at least one of your claims.

Case 1b:

For the Case 1, if Z improves (better results, easier for B,C,D components) the invention a lot, does this new invention infringe my invention?

Still infringes. Just because Z improves things doesn't change the fact that the product infringes if it implements every aspects of at least one of your claims.

Case 1c:

For the Case 1, if Z doesn't improve the invention a lot, does this new invention infringe my invention?

Just like 1b, it still infringes.

Case 2:

If the Z component is added before A or after D, does his new invention infringe my invention?

Order doesn't matter if the product implements each and every aspect of at least one claim in your patent. Still infringes.

The thing to understand about patents that improve upon an existing patent is that while the improvement can be found to be worthy of a patent, that doesn't imply freedom to operate if an existing patent is infringed upon. If, however your patent's claim implements step A, B, C and D and another person figures out a way to make their product work using only steps A, B and D, then they don't infringe since they don't implement each and every aspect of your patent's claim.

Let me reiterate that I am not a lawyer and this is not a legal opinion. Even if I were, you shouldn't rely on internet Q&A sites for legal decisions. As always, you should consult with a qualified attorney.