In September 1968 plaintiff Canadian Filters (Harwich) Limited, a Canadian corporation, hereinafter Filters, filed in the district court for the District
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of Massachusetts a complaint seeking a declaratory judgment against Lear-Sieg-ler, Inc., a Delaware corporation, hereinafter Lear, to the effect that Lear’s U. S. Patent No. 3,044,557 and Lear’s corresponding and very similar Canadian Patent No. 666,465 were invalid and were not being infringed by Filters’ manufacture in Canada and sale in the United States of certain fans. Three weeks lаter Lear sued Filters in the Exchequer Court in Canada for infringement of its Canadian patent. Filters moved in the district court for an injunction аgainst the prosecution of the Canadian suit. Lear responded by moving for a dismissal of the portion of Filters’ complaint that wаs based upon the Canadian patent on the ground that the “act of state” doctrine, Banco Nacional de Cuba v. Sabbаtino, 1964,
It appears that for some time prior to Septеmber 1968 the parties had been in disagreement regarding the propriety of Filters’ conduct, more exactly, perhaps, as to the validity of Lear’s patents. The present question is whether Filters, as a result of a three weeks’ start so far as litigation is conсerned, can delay, if not prevent, Lear from determining the validity of its Canadian patent in the Canadian courts. Filters’ position is that since it was the first in court, Lear is “vexatious” whereas Filters is to be commended for its “attempt to finally settle this controversy at one time.” 2 It goes so far as to claim that Lear should be grateful for the injunction, since it “cannot be hurt * * * and may well benefit,” and even the Exchequer Court should be gratified because its “ease load * * * has been, at last temporarily, and perhaps permanently, reduced.”
Rather than congratulate Filters for its private and public benefactions, unsought and unappreciated аt least so far as Lear is concerned, and, at best, of no value to the Exchequer Court, which is capable of staying its own рroceedings if it wishes to, we observe that fundamental principles have been lost sight of. The issue is not one of jurisdiction, but one, аlmost as important when a foreign sovereign is involved, of comity. The presence of the parties confers on the district court jurisdiction to act, Cole v. Cunningham, 1890,
Doubtless there are times when comity, a blend of courtesy and expedience,
3
must give way, for example when
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the forum seeks to enforce its own substаntial interests, or in limited circumstances when relitigation would cover exactly the same points, as, for example when both suits are in rem, and the burden of a second suit thus renders reliance on res judicata alone inappropriate. However, these exceptions do not apply to this case where the subject matter of the foreign suit is a separate, independent foreign patent right. Sperry Rand Corp. v. Sunbeam Corp., 7 Cir., 1960,
Although Filters, a Canadian corporation, sells its products in the United States, in order to continue its Canadian manufacture it must succeed under both patents. Boesch v. Graff, 1890,
The injunction is vacated and the action is remanded to thе District Court for further proceedings not inconsistent herewith.
Notes
. Filters makes the suggestion in its brief that apparently Lear is content with the court’s own treatment of the Canadian patent as it has not appealed from that part of the order. This suggestion is gratuitous, if not disingenuous, since, as Lear points out, that action is unappealable. 28 U.S.C. §§.1291, 1292.
. How it settles it “at one time” is not made clear, sinсe, coneededly, the district court plans to litigate the United States patent separately.
. As we said in Hayes Indus., Inc. v. Caribbean Sales Associates, Inc.,
supra,
