By Charles L. Gholz2Introduction
Members of the interference bar have been telling their clients and prospective
clients for years that, in many situations, provoking an interference is preferable to defending an
infringement action. Among the arguments that they have used are that interferences are likely
to be far less expensive (I’ve said that a full-blown interference is likely to cost one-fifth to one-
tenth what a full blown infringement action would cost), faster (the BPAI concludes the overwhelming
majority of interferences in less than two years), and decided in a more rational fashion (no juries! And
decisions by techie judges).3 Moreover, if you represent a prospective defendant in an
infringement action, it’s good to know that, in an interference, the patentee’s claims are
not entitled to a presumption of validity and that, except for the issue of fraud/inequitable conduct, your
burden of proof on an invalidity/unenforceability issue is only the preponderance of the evidence,
rather than clear and convincing evidence. To those long-standing reasons we can now add
another: You can prevail in an interference (by which I mean that you can obtain a judgment
cancelling your opponent’s claims) on a ground that you can’t even raise as a defense in
an infringement action.
What Aristocrat Held