en

Publications / Attorney Publications

Application of the Doctrine of Equivalents and the Dedication Rule in Patent Infringement Case for Method Claims

2016-04-28

Shundi CHEN v. Lexueer Co., Ltd. (Civil Judgment (2013) Min Ti Zi No. 225 by the Supreme People’s Court on December 25, 2013)

The extent of protection for an inventioCXVZCXVVCVCVXVCVn patent includes not only the extent determined by the technical features literally recited in the claims, but also the extent determined by the equivalent technical features. For a method claim including a plurality of steps, in order to determine whether the order of the steps acts to define the extent of protection for the claim, and to determine whether the doctrine of equivalents should be applied if no literal infringement is established for the steps were performed in a different order, one should determine whether such steps have to be performed in a particular order, and whether such a different order will produce a substantive difference in terms of technical function or technical effects. Besides, the dedication rule applies also to infringement of a method claim: a technical solution which is recited in the description of the patent but not reflected in the claims cannot be included in the extent of protection for the patent.

 

Shundi CHEN has an invention patent entitled “Manufacturing method of a plastic-cloth hot-water bag”. Claim 1 of the patent reads:

1.  A manufacturing method of a plastic-cloth hot-water bag, the plastic-cloth hot-water bag being composed of a bag body, a bag mouth, and a bag plug, the bag body having an interior layer (4), an exterior layer (3), and a thermal insulating layer (5), the bag body having an adhered edge (6), the bag plug being a threaded plug seat (8) and a threaded plug lid (9), the threaded plug seat (8) having a composite layer (8’) at an exterior wall, the threaded plug lid (9) having a sealed gasket (10), the threaded plug seat (8) in the bag plug (2) being made of a polypropylene material, the composite layer (8’) being made of a polyvinyl chloride material, the sealed gasket (10) being made of a silicone material, the method comprising:

Step 1: first, providing material for the interior layer, the exterior layer and the thermal insulating layer;

Step 2: stacking the interior layer, the thermal insulating layer and the exterior layer in order to form a combined layer;

Step 3: folding the combined layer, and applying a high-frequency heat-sealing machine to perform high-frequency heat adhesion to edges of the two combined layers in accordance with a shape of the hot-water bag;

Step 4: cutting to separate hot-water bags that were subjected to the high-frequency heat adhesion;

Step 5: forming the threaded plug seat (8) from a polypropylene material by injection molding, placing the threaded plug seat (8) as an insert in a model, and forming the composite layer (8’) exterior to the threaded plug seat (8) from a polyvinyl chloride material by a second injection molding;

Step 6: placing the threaded plug seat having the composite layer into the bag mouth to contact the interior layer, and applying the high-frequency heat-sealing machine to perform heat adhesion to the bag mouth and the composite layer of the threaded plug seat;

Step 7: trimming the bag body of the hot-water bag;

Step 8: forming the threaded plug lid (9) from a plastic material by injection molding;

Step 9: forming the sealed gasket (10) from a silicone material by injection molding;

Step 10: after assembling the sealed gasket (10) and the threaded plug lid (9) with each other, screwing them into the threaded plug seat (8);

Step 11: performing a pressure test by filling compressed air into the hot-water bag; and

Step 12: packaging.

 

Lexueer Co., Ltd. manufactured and sold hot-water bags with the above described structure. It was determined that in order to manufacture this kind of hot-water bag, the manufacturing method will included all the steps in claim 1 of the above patent. The alleged infringer held that Steps 6, 7, 8 and 10 in the alleged infringing method are respectively same to Steps 7, 6, 11 and 10 in claim 1 of the patent, but they are in a different order, and therefore the method does not fall within the extent of protection of the patent.

 

Both the first instance and second instance courts held that though Steps 6, 7 and Steps 8, 10 in the alleged infringing method involve different order than Steps 6, 7 and Steps 10, 11 in claim 1 of the patent, there is no substantial difference in the technical features and technical effects, and the alleged infringing method includes all the essential technical features of the patent.

 

The alleged infringer filed a request for retrial to the Supreme People’s Court and held that Steps 6, 7 in the alleged infringing method were in a reversed order as compared with the corresponding steps in claim 1 of the patent, and so did Steps 10, 11; such a change in the order of the steps brought a different technical effect. What was claimed in the patent was a manufacturing method of a product, both the steps themselves and the order of the steps in the method claim should act to define the extent of protection of the patent right. Further, the description of the patent described a reversed order of Steps 10 and 11; based on the dedication rule, this order of steps described in the description should not be included in the extent of protection of the patent. Therefore, the alleged infringing method with the changed order of steps did not fall within the extent of protection of the patent.

 

The Supreme People’s Court held that for Steps 6, 7 in claim 1, performing the two steps were not necessarily in that order, and the reversed order of the two steps did not produce a substantive difference in terms of technical function and technical effect. Thus, the changed steps in the alleged infringing method and Steps 6, 7 in claim 1 of the patent were equivalent technical features. For Steps 10, 11 in claim 1, however, exchanging the two steps did produce such technical effects as reduced operations, saved time, and an improved efficiency. Therefore the difference produced by exchanging the two steps was substantive in terms of technical effect, and the exchanged steps were not equivalent to Steps 10, 11 in claim 1 of the patent. The description of the patent explicitly described in page 3 that Steps 10, 11 can be exchanged; however the exchanged steps were not reflected in the claims. According to the dedication rule, the exchanged steps could not be brought into the extent of protection of the patents. Therefore, the alleged infringing method was neither same nor equivalent to the method of the patent, and did not fall within the extent of protection of the patent.

 

Interpretation and Analysis

This case involves application of the doctrine of equivalents and the dedication rule in a patent infringement case, especially in case of a change of order being made to steps in a method claim.

 

In order to make up for the disadvantages in determining the boundary of a patent right totally with the literal meaning of a claim, many countries apply the doctrine of equivalents to provide a proper expansion to the extent of protection of a claim determined by its literal meaning. The actual extent of protection of a claim includes not only that covered by its literal meaning, but also the extent expanded by applying the doctrine of equivalents. In China, the doctrine of equivalents also applies in patent infringement cases.

 

According to Article 17, Paragraph 2 of Several Provisions of the Supreme People’s Court on Issues Relating to Application of Law to Adjudication of Cases of Patent Disputes, “the extent of protection of a patent right should be determined by all the technical features stated in the claim, including the extent as determined by the features equivalent to the technical features. The equivalent features refer to the features which use substantially the same means, perform substantially the same function and produce substantially the same effect as the stated technical features and which can be contemplated by a person ordinarily skilled in the art without an inventive effort”.

 

Besides, Guidelines for Patent Infringement Determination issued by the Beijing Higher People’s Court in 2013 provides in Article 49: replacement between equivalent features should be replacement between specific and corresponding features, rather than replacement between complete technical solutions.

 

According to the above provisions, technical feature is the unit for determining equivalent objects. This is easy to understand for an apparatus claim. However, as to a method claim, technical features are the steps of a method claim, and can the order of the steps be regarded as a “technical feature” for the application of the doctrine of equivalents? The answer is yes. From this case, it can be seen that the Supreme People’s Court makes it clear that in infringement determination for a method claim, the doctrine of equivalents applies also to the order of the steps.

 

In the present case, the accused infringer held that the exchange to Steps 6, 7 in claim 1 of the patent could save the space that would be occupied by the products to be processed in subsequent procedures, improve the manufacturing speed and accuracy, and enable the products to enter a test procedure directly. However, the retrial court held that performing the two steps were not necessarily in that order, whichever of trimming and heat adhesion being first performed had no influence on the whole technical solution, and exchange of the two steps did not produce a substantive difference in terms of technical function and technical effect. The exchanged steps and the steps not exchanged thus were equivalent technical features. For the exchange to Steps 10, 11 in claim 1 of the patent, the court held that as compared with the alleged infringing method in which a pressure test was performed first and the threaded plug lid was then assembled, Steps 10 and 11 in claim 1 of the patent in fact required more operations in the pressure test, resulting in increased operation time and a lower efficiency. Therefore, exchanging Steps 10 and 11 did produce the technical effects of reduced operations, saved time, and an improved efficiency, as the accused infringer submitted. Therefore the difference produced by exchanging the two steps was substantive in terms of technical effect, and the exchanged steps were not equivalent to Steps 10, 11 in claim 1 of the patent.

 

As the judgment of the case indicates, under such a situation that the order of steps in a method claim is changed and no literal infringement is established as a result, the criterion on whether the doctrine of equivalents can be applied is whether these steps must be performed in a certain order and whether the changing of the order will bring a substantive difference in terms of technical function or technical effect.

 

The case also involves the application of the dedication rule. In a patent infringement case, if the technical solution of the alleged infringing product is disclosed in the description of the patent but does not fall within the literal extent of protection of the claim, then the patentee cannot rely on infringement under the doctrine of equivalents. The technical solution that the patentee disclosed in description but did not claim in the claims is deemed as being dedicated to public. This is so-called dedication rule.

 

According to Article 5 of Several Provisions of the Supreme People’s Court on Issues Relating to Application of Law to Adjudication of Cases of Patent Disputes, “for the technical solution only described in the description or depicted in the drawings but not described in the claims, where the patentee brings the technical solution into the extent of protection of the patent right in a patent infringement case, the people’s court should not support”.

 

This judicial interpretation takes the following situation into consideration in setting the dedication rule: in order to obtain a patent right more easily, a patent applicant may sometimes uses a relatively specific feature in claims, and gives it an expanded interpretation in the description and drawings. In infringement cases, the patentee asserts that the expanded portion in the description is an equivalent feature, and thereby unduly expands the extent of protection of the patent right. The patent system should not only protect the interest of patentees, but also maintain the publicity function of claims. Therefore, the dedication rule helps in protecting the publicity of claims, and balancing the interest between patentees and public.

 

In this case, the description described that Steps 10, 11 could be exchanged. Does the accused infringer’s action of exchanging the steps fall within the extent of protection of the patent?

 

According to the provision above, if, by reading the description, a person skilled in the art can understand that the technical solution disclosed but not claimed is particularized for including an alternative to a technical feature in the claims, then such a technical solution is deemed as a donation to the public. The description of the patent explicitly described that Steps 10, 11 can be exchanged, while the exchanged steps are not reflected in the claims. Therefore the exchanged steps cannot be covered by the patent.

 

This case provides a guide for drafting application documents on method patents. In order to avoid getting into an unfavorable situation when enforcing the right, attention should be paid to the following aspects.

 

(1) Unless necessary, the order of steps should not be defined in claims, e.g. with such words as “first”, “first step”, etc., and words implying that some order would exist for the steps should also be avoided.

(2) If a change to the order of steps does bring a technical effect, such change should be not only mentioned in description, but also brought into the literal extent of protection of the claims.