Germany: Patents -5. Infringement of Patents

Last Updated: 10 February 1998

I. Infringement of Patents

Section 9 Patent Act provides for the basic right of patentee to exclusively use the invention subject to the patent and to forbid others from using it. To find out whether a third party infringes a patent one has to determine the scope of protection of such patent and to establish that the challenged device actually falls within this scope.

1. Scope of a Patent

The definition of how to determine the scope of protection of a patent is prescribed in Section 14 Patent Act. According to this provision the extent of protection conferred by a patent (or patent application) has to be determined by the terms of the claims, however, using the description and drawings to interpret such claims. German courts have continuously stated that they apply the protocol on the interpretation of Article 69 European Patent Convention in this context. This protocol makes clear that in determining the scope of a patent a balance must be struck between the rights of a patentee and the interests of the public at large in a reasonable degree of certainty. This means in German practice that in interpreting the scope of a patent one may not aim at the literal language of the claims alone but, on the other hand, may not invoke everything mentioned in the patent document.

2. Claim Interpretation

The claims of a patent are the starting point for interpretation as well as the decisive basis for determining the extent of protection. Claim 1 of a patent is considered to be the main claim of which the following claims usually derive as subclaims. As a patent comprises an abstract technical teaching and as the claims setting forth this technical teaching are drafted with a view to a person skilled in the art, any interpretation has to be made under the aspect of technique and not semantic. However, only the knowledge available at the time of the filing of the application can be taken into account by a person skilled in the art.

To interpret the claims of a patent, the description and the drawings shall be used. This means that they have always to be checked but can not extend the scope of protection if the claims do not make reference to elements mentioned in the description or the drawings. If there is a contradiction as to the scope of protection between the claim and a drawing the claim always prevails.

To interpret a patent one has further to distinguish between the two types of patents, product and process patents. As far as product claims are concerned the patent covers all infringing products independent of how they were produced. On the other hand, a product by process claim only protects products which have been manufactured using the patented process.

3. Infringing Acts

A patent is clearly infringed if the challenged device or process is identical to the invention covered by the patent, i.e. if it falls directly under the claims of the patent. However, the protection granted is not limited to the devices and processes covered by the literal terms of the claims. Protection is also extended to equivalents because no-one is in the position to draft claims in a way that will protect against all possible infringing acts. The doctrine of equivalence covers all means that have an effect similar to the means covered by the patent claim, if a person skilled in the art will through his recognition of a specific means used to achieve a specific effect find a different means that achieves the same effect. Again the knowledge at the date of application or the priority date is decisive. To determine whether an equivalent infringement is given is one of the most difficult and disputed issues in practice.

The Federal Supreme Court has established two prerequisites for the extension of a patent claim to equivalent means. First, the means used by the infringer must have the same technical function to reach the same technical result. This would no longer be the case if both means serve different tasks. Second, the means are deemed equivalent if a person skilled in the art could derive it - as of the day of the application - as obvious from the claims stated by use of description and drawings. Although this is not achieved if finding the equivalent means requires an inventive step by a person skilled in the art, it still fulfils the test if some thinking is necessary to find the equivalent means.

Following this, a defendant in an infringement case may accordingly argue that an equivalent infringement is not present because the allegedly infringing device was obvious in the view of prior art. Further, the defendant may bring forward that the device in dispute would represent a patentable invention at the time of filing the patent compared to the patented invention.

II. Legal Procedure of Infringement Cases

1. General

According to Section 139 para. 1 and para. 2 Patent Act a patentee is entitled to sue an infringer for an injunction or for damages before the civil courts. Special chambers at the Regional Courts ("Landgerichte") have exclusive jurisdiction without regard to the value in dispute (Section 143 para. 1 Patent Act).

In any legal action a patentee initiates against an infringer before a civil court he has to show that an infringement is given. Patentee may rely on the assistance of an expert witness who has to be appointed by the court. With regard to product claims it is sufficient for plaintiff to prove that the product of the infringer falls within the scope of the patent. In case of process claims to produce a product plaintiff only has to establish similarity between a product manufactured by the patented process and the allegedly infringing product. The burden of proof to prove the contrary is on the defendant. If plaintiff showed that infringement happened in the past, there exists a prima facie evidence that the defendant will infringe the patent in future as well.

As defense the defendant may bring forward a number of arguments, mainly those which are listed in Section 11 Patent Act. These defenses are personal use (Section 11 No. 1), experimental use (Section 11 No. 2), preparation of a medicine (Section 11 No. 3) and territorial limitations as per Section 11 Nos. 4 through 6 Patent Act. The allegation that the patent is not valid is no defense in an infringement suit because the court in an infringement action does not have jurisdiction to decide about the validity of a patent. The defendant may, however, initiate nullity proceedings with the Federal Patent Court. As the nullity action usually lasts longer than the infringement case the defendant may ask for a suspension of the infringement proceedings. The stay will be ordered by the court, if it takes the view that the nullity action is likely to be successful.

After a judgement is rendered by a court of first instance the defeated party may appeal the decision before the Court of Appeals. On further appeal the case will be finally determined by the Federal Supreme Court.

2. Remedies in an Infringement Suit

The claim of patentee may be directed to different remedies. He may want to receive an injunction against the infringer, claim for damages or compensation or combine these claims in one proceedings.

a) Injunction

The right of patentee for an injunction follows from Section 139 para.1 Patent Act. To receive an injunction against an infringer patentee may apply for a preliminary injunction or a permanent injunction. While the proceedings for a permanent injunction are the regular action before the courts (complaint, defense brief, oral hearing, witnesses etc.) a preliminary injunction enjoining the infringer to use the infringing product any more is the exception. In this proceedings the injunction may be granted ex parte upon the complaint of patentee alone - which, however is unusual in patent infringement cases where normally an oral hearing is scheduled. In this complaint patentee has to show beyond any reasonable doubt that the patent is valid and that it has been infringed prima facie.

b) Damages and Compensation

Section 139 para. 2 Patent Act provides for damages in case of intentional or negligent infringement. As courts consider a culpable infringement already to be given if an infringer could have taken notice of the patent before manufacturing its product, almost every infringement will be considered to have occurred at fault. In order to enable patentee to determine the damages suffered, a court will order the infringer to provide the necessary information regarding the infringing acts (number of products manufactured and shipped, advertisements etc.). Patentee may choose among three options for calculating his damages. He may ask for the actual damages caused by the infringing acts (including lost profits). Second, he may base his claim for damages on usual royalties and, finally, he may claim the profits obtained by the infringer.

In addition to the existing rules of damage assessment it has been established by the Federal Supreme Court that a patentee may also claim compensation according to the rules of unjust enrichment. This claim does not depend on any fault of the infringer and leads to payment of a reasonable royalty only.

While damages are only granted for the time after the grant of the patent has been published, a patentee may claim for a compensation according to Section 33 para. 1 Patent Act, if an infringer has culpably used the subject of a patent application after the application has been published. The claim for compensation would again involve payment of a reasonable royalty, however, less than a usual royalty.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on

Click to Login as an existing user or Register so you can print this article.

Some comments from our readers…
“The articles are extremely timely and highly applicable”
“I often find critical information not available elsewhere”
“As in-house counsel, Mondaq’s service is of great value”

Up-coming Events Search
Font Size:
Mondaq on Twitter
Register for Access and our Free Biweekly Alert for
This service is completely free. Access 250,000 archived articles from 100+ countries and get a personalised email twice a week covering developments (and yes, our lawyers like to think you’ve read our Disclaimer).
Email Address
Company Name
Confirm Password
Mondaq Topics -- Select your Interests
 Law Performance
 Law Practice
 Media & IT
 Real Estate
 Wealth Mgt
Asia Pacific
European Union
Latin America
Middle East
United States
Worldwide Updates
Check to state you have read and
agree to our Terms and Conditions

Terms & Conditions and Privacy Statement (the Website) is owned and managed by Mondaq Ltd and as a user you are granted a non-exclusive, revocable license to access the Website under its terms and conditions of use. Your use of the Website constitutes your agreement to the following terms and conditions of use. Mondaq Ltd may terminate your use of the Website if you are in breach of these terms and conditions or if Mondaq Ltd decides to terminate your license of use for whatever reason.

Use of

You may use the Website but are required to register as a user if you wish to read the full text of the content and articles available (the Content). You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these terms & conditions or with the prior written consent of Mondaq Ltd. You may not use electronic or other means to extract details or information about’s content, users or contributors in order to offer them any services or products which compete directly or indirectly with Mondaq Ltd’s services and products.


Mondaq Ltd and/or its respective suppliers make no representations about the suitability of the information contained in the documents and related graphics published on this server for any purpose. All such documents and related graphics are provided "as is" without warranty of any kind. Mondaq Ltd and/or its respective suppliers hereby disclaim all warranties and conditions with regard to this information, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. In no event shall Mondaq Ltd and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of information available from this server.

The documents and related graphics published on this server could include technical inaccuracies or typographical errors. Changes are periodically added to the information herein. Mondaq Ltd and/or its respective suppliers may make improvements and/or changes in the product(s) and/or the program(s) described herein at any time.


Mondaq Ltd requires you to register and provide information that personally identifies you, including what sort of information you are interested in, for three primary purposes:

  • To allow you to personalize the Mondaq websites you are visiting.
  • To enable features such as password reminder, newsletter alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our information providers who provide information free for your use.

Mondaq (and its affiliate sites) do not sell or provide your details to third parties other than information providers. The reason we provide our information providers with this information is so that they can measure the response their articles are receiving and provide you with information about their products and services.

If you do not want us to provide your name and email address you may opt out by clicking here .

If you do not wish to receive any future announcements of products and services offered by Mondaq by clicking here .

Information Collection and Use

We require site users to register with Mondaq (and its affiliate sites) to view the free information on the site. We also collect information from our users at several different points on the websites: this is so that we can customise the sites according to individual usage, provide 'session-aware' functionality, and ensure that content is acquired and developed appropriately. This gives us an overall picture of our user profiles, which in turn shows to our Editorial Contributors the type of person they are reaching by posting articles on Mondaq (and its affiliate sites) – meaning more free content for registered users.

We are only able to provide the material on the Mondaq (and its affiliate sites) site free to site visitors because we can pass on information about the pages that users are viewing and the personal information users provide to us (e.g. email addresses) to reputable contributing firms such as law firms who author those pages. We do not sell or rent information to anyone else other than the authors of those pages, who may change from time to time. Should you wish us not to disclose your details to any of these parties, please tick the box above or tick the box marked "Opt out of Registration Information Disclosure" on the Your Profile page. We and our author organisations may only contact you via email or other means if you allow us to do so. Users can opt out of contact when they register on the site, or send an email to with “no disclosure” in the subject heading

Mondaq News Alerts

In order to receive Mondaq News Alerts, users have to complete a separate registration form. This is a personalised service where users choose regions and topics of interest and we send it only to those users who have requested it. Users can stop receiving these Alerts by going to the Mondaq News Alerts page and deselecting all interest areas. In the same way users can amend their personal preferences to add or remove subject areas.


A cookie is a small text file written to a user’s hard drive that contains an identifying user number. The cookies do not contain any personal information about users. We use the cookie so users do not have to log in every time they use the service and the cookie will automatically expire if you do not visit the Mondaq website (or its affiliate sites) for 12 months. We also use the cookie to personalise a user's experience of the site (for example to show information specific to a user's region). As the Mondaq sites are fully personalised and cookies are essential to its core technology the site will function unpredictably with browsers that do not support cookies - or where cookies are disabled (in these circumstances we advise you to attempt to locate the information you require elsewhere on the web). However if you are concerned about the presence of a Mondaq cookie on your machine you can also choose to expire the cookie immediately (remove it) by selecting the 'Log Off' menu option as the last thing you do when you use the site.

Some of our business partners may use cookies on our site (for example, advertisers). However, we have no access to or control over these cookies and we are not aware of any at present that do so.

Log Files

We use IP addresses to analyse trends, administer the site, track movement, and gather broad demographic information for aggregate use. IP addresses are not linked to personally identifiable information.


This web site contains links to other sites. Please be aware that Mondaq (or its affiliate sites) are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of these third party sites. This privacy statement applies solely to information collected by this Web site.

Surveys & Contests

From time-to-time our site requests information from users via surveys or contests. Participation in these surveys or contests is completely voluntary and the user therefore has a choice whether or not to disclose any information requested. Information requested may include contact information (such as name and delivery address), and demographic information (such as postcode, age level). Contact information will be used to notify the winners and award prizes. Survey information will be used for purposes of monitoring or improving the functionality of the site.


If a user elects to use our referral service for informing a friend about our site, we ask them for the friend’s name and email address. Mondaq stores this information and may contact the friend to invite them to register with Mondaq, but they will not be contacted more than once. The friend may contact Mondaq to request the removal of this information from our database.


From time to time Mondaq may send you emails promoting Mondaq services including new services. You may opt out of receiving such emails by clicking below.

*** If you do not wish to receive any future announcements of services offered by Mondaq you may opt out by clicking here .


This website takes every reasonable precaution to protect our users’ information. When users submit sensitive information via the website, your information is protected using firewalls and other security technology. If you have any questions about the security at our website, you can send an email to

Correcting/Updating Personal Information

If a user’s personally identifiable information changes (such as postcode), or if a user no longer desires our service, we will endeavour to provide a way to correct, update or remove that user’s personal data provided to us. This can usually be done at the “Your Profile” page or by sending an email to

Notification of Changes

If we decide to change our Terms & Conditions or Privacy Policy, we will post those changes on our site so our users are always aware of what information we collect, how we use it, and under what circumstances, if any, we disclose it. If at any point we decide to use personally identifiable information in a manner different from that stated at the time it was collected, we will notify users by way of an email. Users will have a choice as to whether or not we use their information in this different manner. We will use information in accordance with the privacy policy under which the information was collected.

How to contact Mondaq

You can contact us with comments or queries at

If for some reason you believe Mondaq Ltd. has not adhered to these principles, please notify us by e-mail at and we will use commercially reasonable efforts to determine and correct the problem promptly.