Mueller The mere fact of amendment, as long as it narrowed the scope of a claim limitation for any statutory reason, works an absolute bar to a finding of equivalency as regards that limitation. Coverage over subsequently- developed but equivalent technology, not even fathomed at the time of the patentee’s filing, is consequently extinguished under Festo
Narrower claims? New filings will surely present greater numbers of narrower claims, and more thorough prior art searches will be required pre-filing in order to better predict what claims will be allowable without amendment. Applicants will be highly motivated to appeal rejections rather than amend their claims, thus compounding an already immense backlog at the PTO Board of Appeals. Although the resulting prosecution costs in the form of extended attorney time and higher PTO fees will impact all applicants, small-entity/start-up technology firms and solo inventors who can least afford them will predictably be the most prejudiced
Mueller Whether the rule of Festo works permanent structural harm to the patent system or is corrected on certiorari is now in the hands of the Supreme Court.
DEATH SENTENCE TO EQUIVALENTS? These new rules, which limit the application of the doctrine of equivalents, promise to change the practice of patent law and will affect the behavior of competitors for years to come. The new rules increase: (1) the resources to be invested the application drafting process, (2) the need for careful and thoughtful prosecution practice, and (3) the importance of the Markman hearing in patent litigation.
THE FOUR HOLDINGS OF FESTO (1) Prosecution history estoppel applies with any narrowing amendment made to deal with any statutory ground, not just amendments made in response to prior art rejections, (2) voluntary amendments, including preliminary amendments are treated the same as amendments required by the examiner, (3) if prosecution history estoppel applies, the patentee is not entitled to any scope of equivalents as to the amended element, and (4) if an amendment is made without explanation, no range of equivalents is available.
Reason related to patentability For the purposes of determining whether an amendment gives rise to prosecution history estoppel, a "substantial reason related to patentability" is not limited to overcoming or avoiding prior art, but instead includes any reason which relates to the statutory requirements for a patent. Therefore, a narrowing amendment made for any reason related to the statutory requirements for a patent will give rise to prosecution history estoppel with respect to the amended claim element.
Voluntary amendments Voluntary claim amendments are treated the same as other amendments. Therefore, a voluntary amendment that narrows the scope of a claim for a reason related to the statutory requirements for a patent will give rise to prosecution history estoppel as to the amended claim element.
Voluntary Arguments Arguments made voluntarily during prosecution may give rise to prosecution history estoppel if they evidence a surrender of subject matter. E.g., KCJ Corp. v. Kinetic Concepts, Inc., 223 F.3d 1351, 1359-60, 55 USPQ2d 1835, 1841-42 (Fed. Cir. 2000) (concluding that "KCJ's statements [during prosecution] reflect a clear and unmistakable surrender" of subject matter that cannot be reclaimed through the doctrine of equivalents);
En banc 3 "[W]hen a claim amendment creates prosecution history estoppel, no range of equivalents is available for the amended claim element".
Harold C. Wegner says Clearly, the denial of any range of equivalents contradicts generations of Supreme Court case law that are perhaps disregarded only because of their vintage: The conflicts are pointed out by Circuit Judge Michel (joined by Circuit Judge Rader). It is doubtful, however, that the Supreme Court would revisit Festo on this issue.
Features that Remain Unamended A claimed Widget may have elements W1+W2+W3. If the amendment is made that narrows W2 to W2', then by simply making the amendment and an argument focusing solely upon element W2', then there is estoppel to bar any equivalency for any other W2, but there still remains open the possibility for equivalency for the unamended elements W1 and W3.
Past in terrorem effect The Court majority was trying to limit the in terrorem effect of having a jury decided issues of equivalence. The uncertainty created by giving the technically unsophisticated jurors the ability to award multimillion dollar damages gave patentees a powerful weapon. Competitors, faced with the uncertainty of a jury determining the scope of equivalents, simply would stay out of markets in the face of a bullying patentee.
Markman and Festo The Festo decision increases the importance of the Markman hearing. Markman hearings have already become critically important events in most patent suits. A court could interpret a critical claim element, address ancillary prosecution history estoppel issues, and resolve many cases without need for trial.
Strategy Instead of filing "the" case and relying upon the doctrine of equivalents, an evolutionary approach should be adopted. The provisional application system provides a very convenient weapon for the pioneer inventor: Every new development is made the subject of a provisional application At the first anniversary of the first filing, that first filing together with all the subsequent provisionals are cobbled together into a massive filing under the Patent Cooperation Treaty (and the Paris Convention) to provide the best scope of protection possible on a global basis.
Evolution The evolutionary approach to patent filing offers an additional advantage—each of the embodiments disclosed in the provisional applications can be included in the PCT filing. This results in a specification that broadly discloses the claimed invention and includes several working embodiments. Such a specification is likely to provide written description support for a broad range of claims of varying scope. It will also help counteract Federal Circuit’s tendency to construe claims narrowly when the specification discloses a single working embodiment. See, e.g., Watts v. XL Sys., Inc. 2000 WL 1693057 (Fed. Cir. Nov. 14, 2000).
Action items (1) Before the application is filed, all of the available prior art must be considered. Pre-filing prior art searches have also become more advisable. (2) Applicants should make full use of the three independent claims and the twenty total claims included with the filing fee. The goal is the draft multiple sets of claims of varying scope. The goal is to file at least one claim that is allowable as written. (3) If the original claims of the patent are allowed as filed, there will be a freedom from prosecution history estoppel, unless there have been arguments of criticality made relating to patentability
Statements Prior to Festo, the panel opinions of the Federal Circuit had generally approved the application of prosecution history estoppel against unamended claims based upon argumentation of criticality of a particular feature. This viewpoint is strongly approved in the Festo majority opinion. Therefore, arguments in the specification, particularly the "Background of the Invention", must be very carefully thought out. Information Disclosure Statements should also be very carefully drawn so as to only paraphrase (or better yet quote from) what the prior art reference states, without comparative statements. To do otherwise is to again invite foreclosure of the doctrine of equivalents.
Amendments (1) Change as few limitations as possible to address the Examiner’s rejections. (2) Confine amendments to limitations where, for technical or commercial reasons, there is no need for the doctrine of equivalents. (3) Explain the reason for all amendments. In particular, if amendment is intended to broaden the scope of a claim limitation, say so clearly. (4) Carefully identify which claim limitations and claims are being discussed in remarks concerning a particular amendment. See Johnson Worldwide Assocs., Inc. v. Zebco Corp., 175 F.3d 985 (Fed. Cir. 1999). (5) If the Examiner indicates that a dependent claim would be allowable and is only objected to because it depends from a non-allowed independent claim, rewrite the dependent claim in independent form. Do not add the claim limitation to the dependent claim. (6) If a limitation is broadly disclosed in the specification, consider rewriting amended claim elements in means-plus-function form.
Shumaker Strategy Narrow Claims Hierarchy of Independent Claims Multiple Parallel Applications Characterizing Remarks Ensure Clarity New Claim Sets Know the Prior Art Varied Terminology Examiner Interviews Declarations
Hierarchy of Independent Claims Independent claims may vary from broad to narrow, and may include a generic claim The Examiner may allow some of the independent claims without the need for amendment. This approach avoids the need to rewrite dependent claims in independent form. Instead, they would be drafted as independent claims from the beginning. Unknown impact of Festo when claims are canceled. In particular, if the prosecutor gives up claim scope by canceling broader, independent claims, Unclear whether an estoppel would be raised against the remaining claims to the extent they merely define incremental limitations over the canceled claims.
Multiple Parallel Applications If one application initially claims the invention very broadly, for example, but requires amendments to obtain allowance, the theory is that the resulting estoppel will not be visited upon the other applications. This assumes that the applications are not legally linked to one another by a claim of priority. If this approach works, the expense of another filing may pay dividends in preserving the availability of the doctrine equivalents. This strategy is an effort to “seal off” applications claiming the invention narrowly from applications claiming the invention more broadly.
Characterizing Remarks Some prosecutors are beginning to advocate a practice contrary to their instincts—distinguish the claim limitations in the record Previously, prosecutors have been trained to say as little as possible Post-Festo, claims that speak for themselves can be a liability if amended, triggering the absolute bar to the doctrine of equivalents. This counter-intuitive tactic would involve characterizing claimlimitations to define differences over the prior art, without actually amending the limitations to indicate those differences.
Question 4 When “no explanation [for a claim amendment] is established,” Warner- Jenkinson, 520 U.S. at 33, 117 S.Ct. 1040, thus invoking the presumption of prosecution history estoppel under Warner-Jenkinson, what range of equivalents, if any, is available under the doctrine of equivalents for the claim element so amended?  We answer Question 4 as follows: When no explanation for a claim amendment is established, no range of equivalents is available for the claim element so amended. This question is answered by Warner-Jenkinson: Where no explanation is established,.... prosecution history estoppel would bar the application of the doctrine [of] equivalents as to that element. Warner-Jenkinson, 520 U.S. at 33 (emphasis added). In answering this question, we affirm what we stated in Sextant, 172 F.3d at 832, 49 USPQ2d at 1875: when “the Warner-Jenkinson presumption is applicable,... the prosecution history estoppel arising therefrom is total and completely `bars’ the application of the doctrine of equivalents as to the amended limitation.”
Look in the file? Page 1890: As discussed above, under Warner-Jenkinson, Festo bears the burden of establishing that the amendment was made for a reason unrelated to patentability. Warner-Jenkinson, 520 U.S. at 40-41. It has failed to do so. Festo admits that there is “[n]o specific mention of the sealing rings” in the prosecution history record. In view of this prosecution history, Festo cannot establish that the amendment that added the pair of sealing rings element was made for a reason unrelated to patentability. Indeed, the prosecution history indicates that the amendment was made for a reason related to patentability.
In re Clement If an applicant amends a broad claim in an effort to distinguish a reference and obtain allowance, but promptly files a continuation application to continue to traverse the prior art rejections, circumstances would suggest that the applicant did not admit that broader claims were not patentable--assuming that the applicant did not ultimately abandon the continuation application because the examiner refuses to withdraw the rejections. 131 F.3d 1464 (CAFC 1997)
Festo Mary Ellen Feehery: strategy of narrow then broad Carl Pierce: Recent Insituform decision BuSpar (buspirone): Bristol Myers v. Mylan (D.D.C.), conversion in the stomach Lunch and CLE March 30, 2001