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Controversy Surrounding the Revised Chapter 9 of the MOPOP

January 1, 2011

Ken Bousfield & Tasha De Freitas

In December 2010, the Canadian Intellectual Property Office (CIPO) released a revised version of Chapter 9 of the Manual of Patent Office Practice (MOPOP), relating to the description requirement for Patent Applications under the Canadian Patent Act (the Act). The revision remains controversial in the patent profession for several reasons:

  • There continues to be concern that the revised Chapter 9 interprets the description requirements under the Act in a manner inconsistent with, and beyond the scope of, the statute and case law.
  • Topics pertaining to obviousness and utility have, inappropriately, been combined with the requirement of description.
  • Chapter 9 continues to take a highly controversial position on the Doctrine of Sound Prediction (which is often important in chemical and biotechnological cases), apparently suggesting that higher standards of description apply than for other inventions. Oddly, the new Chapter 9 concedes that an explanation of the underlying theory of the invention is not required by law, yet it also states it may not be possible to properly express the line of reasoning supporting the sound prediction without including the underlying theory. The premise that a line of reasoning is required in a patent description may itself not be supported in law.
  • The revised Chapter 9 appears to suggest that examiners have the authority to determine the nature of “persons skilled in the art” for purposes of prosecution, notwithstanding that examiners are poorly placed to make such a determination.
  • In the past, the MOPOP was intended to be a helpful neutral guideline, or practical collation and distillation, of the Act, the Patent Rules (the Rules), and the case law for the use of examiners and practitioners. However, re-written Chapter 9 casts substantial doubt upon its own reliability and accuracy and, consequently, diminishes its usefulness as a guide.

In view of the resultant uncertainty, applicants may wish to be even more careful than usual in making sure the specification is highly detailed. The specification should describe multiple embodiments and have multiple examples showing that the inventor was fully possessed of the invention in its broadest aspects, should describe uses of the product, and should provide a careful description of the methods of manufacture and of use.

Finally, in prosecuting applications, applicants may wish to exercise skepticism when reading Chapter 9, and be vigilant in verifying its statements against the base sources of the law: the Act, the Rules, and case law.

Ken Bousfield, B.A.Sc. (Mech. Eng.), LL.B., is a partner with Bereskin & Parr LLP's Patent Practice group. Ken can be reached in Toronto at 416.957.1650 or

Tasha De Freitas, Student-at-Law at Bereskin & Parr LLP, from the University of Windsor, can be reached in Toronto at

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