Claims for Residual Damages Under German Law

Last month I blogged about an article by Michael Nieder titled Europäische (Bündel)Patente--Restschadensersatzanspruch adé? ("European (Bundle) Patents--Farewell to Residual Damages Claims?") in the January 2016 issue of Mitteilungen der deutschen Patentanwälte (pp. 1-3), which discusses, among other things, whether article 72 of the Agreement on a Unified Patent Court, which mandates a five-year statute of limitations for infringement claims, eliminates the ten-year statute of limitations for underlying residual damages claims under German law.  As I wrote at the time (see here): 

The author explains that, under section 199(1) of the German Civil Code, a claim for damages for the infringement of a German patent or the German portion of a European Patent normally must be brought within three years ("Unless another commencement of limitation of is determined, the standard limitation period commences at the end of the year in which . . . 1.  the claim arose and 2.  the obligee obtains knowledge of the circumstances giving rise to the claim and of the identity of the obligor, or would have obtained such knowledge if he had not shown gross negligence").  However, the second sentence of section 141 of the German Patent Act states "Where the person obliged has obtained something as a consequence of the infringement at the expense of the entitled person, section 852 of the German Civil Code shall apply mutatis mutandis," and section 852 states "If by a tort the person liable to pay compensation obtains something at the cost of the injured person, then even after the claim to compensation for the damage arising from a tort is statute-barred he is obliged to make restitution under the provisions on the return of unjust enrichment. This claim is statute-barred ten years after it arises, or, notwithstanding the date on which it arises, thirty years after the date on which the act causing the injury was committed or after the other event that triggered the loss." 

Similarly, in a post I published in 2013 I noted that:

In Germany, the statute of limitations for filing an action for patent infringement is governed by article 141 of the Patent Act.  WIPO’s translation of this provision reads:

As regards the period of limitation for claims due to infringement of a patent right, the provisions of Part 5 of Book 1 of the Civil Code shall apply mutatis mutandis. If the infringer has gained something through the infringement at the expense of the entitled party, Section 852 of the Civil Code shall be applicable mutatis mutandis.

Focusing on sentence 1, the general statute of limitations for filing a patent infringement claim is three years.  See Thomas Kühnen, Patent Litigation Proceedings in Germany:  A Handbook for Practitioners ¶ 1554,at 389 (6^th ed. Frank Peterreins tr. 2013); Benkard, Patentgesetz § 141 ¶ 4, at 1504 (10^th ed. 2006).  But the second sentence provides a second opportunity to file a claim for damages, after the three-year period has lapsed.  Here is the text of the referenced section of the Civil Code (BGB § 852) (English translation can be found here, German original here):

If by a tort the person liable to pay compensation obtains something at the cost of the injured person, then even after the claim to compensation for the damage arising from a tort is statute-barred he is obliged to make restitution under the provisions on the return of unjust enrichment. This claim is statute-barred ten years after it arises, or, notwithstanding the date on which it arises, thirty years after the date on which the act causing the injury was committed or after the other event that triggered the loss.

So even after the three-year period, the patent owner may get to file a claim, but for what?  The term used for the damages the patent owner may recover under these circumstances is Restschadensersatz, or residual damages.  Prevailing opinion is that these damages consist of a reasonable royalty only.  See Benkard Patentgesetz, § 141 ¶ 6, at 1505-06.  The argument appears to be that the only benefit the infringer derived at the expense of the entitled party is the royalty it didn’t pay.  For a contrary opinion, however, see Matthias Hülsewig, Der Restschadensersatzanspruch im Patentrecht—beschränkt auf die angemessene Lizenzgebühr?, GRUR 2011, 673, arguing that the patentee should have the option of recovering the infringer’s profit or a reasonable royalty.

A few weeks back Dr.  Hülsewig kindly emailed me a copy of a 2015 opinion of the German Federal Supreme Court in a copyright matter, in which the court states that the question of whether BGB § 852 permits the recovery of the infringer's profit remains an open question.  See paragraph 34 of Judgment of Jan. 15, 2015, I ZR 148/13 (BGH)--Motorradteile, available here.  In addition, as Dr. Hülsewig pointed out, the new 11th edition of the Benkard treatise on German Patent Law now also takes the position that claims for residual damages are not limited to reasonable royalties but also may include the disgorgement of other pecuniary benefits the infringer has derived ("Daher kann der Rest-Schadensersatzanspruch nicht in jedem Fall auf die (stets geschuldete) angemessene Lizenz beschränkt werden; vielmehr können auch weitere Vermögensvorteile herausverlangt werden" (section 141, p. 1907).  So perhaps we are witnessing a change in the majority view of what claims for residual damages may include under German law--though if Nieder is correct about the effect of the Unified Patent Agreement, in cases involving European patents such claims eventually may be constrained by the five-year statute of limitations.