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Patent Term and Double Patenting

The short version

Two Federal Circuit decisions have to be read together, and reading either alone leads to an expensive mistake in opposite directions. One holds that extra term granted for Patent Office delay can expose a family member to double patenting. The other holds that in the configuration before it, a first-filed and first-issued patent set the ceiling and could not be attacked by later-filed, later-issued relatives that expire earlier.

A third page covers how the Patent Office actually applies the second one during examination, which is narrowly. None of the three is published without the others, on purpose.

Double patenting asks a narrow question: does one patent improperly extend exclusivity past a related one? The answer turns on expiration dates, and expiration dates move when the Patent Office grants extra term for its own delay.

That is where the trouble starts. In re Cellect holds the comparison uses the date after Patent Term Adjustment is added, so time granted as compensation can become the reason a relative is invalid. The instinctive response is to file terminal disclaimers across the family and align the dates.

That instinct is what Allergan exists to stop. Once a patent issues subject to a terminal disclaimer, the surrendered term is not coming back. If the patent in question is the first-filed and first-issued in its family, it sets the ceiling on exclusivity and cannot be an improper extension of anything, so disclaiming would give away term for nothing.

The two errors are mirror images. Read Cellect alone and you disclaim term you did not have to. Read Allergan alone and you skip a disclaimer you needed, past a deadline that does not reopen. Both are expensive and neither is recoverable, which is why these two pages travel together.

The Timing Detail That Decides It

Cellect closed the escape routes a patent owner would reach for: good faith is not reviewable in that posture, and a promise never to split ownership of the family is not evidence that saves anything.

The one that matters operationally is different. A terminal disclaimer cannot be filed once a patent has expired. The remedy exists and then it stops existing, on a date that arrives whether or not anyone is tracking it. Acting reasonably does not reopen the window.

So the analysis that decides whether to disclaim has to happen while the option is still live, which in practice means well before anyone is thinking about it.

The Patent Office reads Allergan more narrowly than patent owners did. In Ex parte Baurin, a precedential agency panel held that the exception applies only where the claims are first-filed, first-issued and later-expiring in a family sharing a patent term filing date, and that this "will rarely, if ever, arise in original examination." It also held that the risk of split ownership supports a rejection on its own, with no term extension in view. That is examination practice rather than law, and the panel invited the Federal Circuit to correct it if it is wrong.

What These Pages Do Not Decide

  • Whether any particular family member is at risk. That depends on filing order, issuance order and expiration dates for the actual patents.
  • Whether to file a terminal disclaimer. It is irreversible in one direction and the deadline is unforgiving in the other.
  • Whether any continuation strategy is sound. Portfolio strategy is legal advice with consequences that cannot be walked back.
  • How a court would rule. One of these three is an agency decision that binds examiners and no judge.

Educational, not legal advice. Every quotation is verified against the court's own opinion, but a holding is not a rule about your portfolio. Consult a qualified patent attorney with the actual family in front of them.