Opportunity for Equivalents in Claim Amendments

by Womble Bond Dickinson
Contact

It is commonly held that the doctrine of equivalents is lost when claim amendments are made during patent prosecution.  That is, any claim amendment that is made during patent prosecution surrenders or gives up elements which are equivalent to those elements claimed in the amendment.  Surrender of the doctrine of equivalents places the burden on the patent Applicant, and the patent practitioner representing the Applicant, to carefully consider any amendments to the claims prior to issuance of the patent (when such occurs).  This principle is neatly summed up in the rulings on the following two cases.

In re Zletz, 893 F.2d 319, 322, 13 USPQ2d 1320, 1322 (Fed. Cir. 1989) (manner of claim interpretation that is used by courts in litigation is not the manner of claim interpretation that is applicable during prosecution of a pending application before the PTO).

Sage Prods., Inc. v. Devon Indus., Inc., 126 F.3d 1420, 1425, 44 USPQ2d 1103, 1107 (Fed. Cir. 1997) (patentee who had a clear opportunity to negotiate broader claims during prosecution but did not do so, may not seek to expand the claims through the doctrine of equivalents, for it is the patentee, not the public, who must bear the cost of failure to seek protection for this foreseeable alteration of its claimed structure).

What does this mean for the patent practitioner?  The claims as originally filed in a non-provisional patent application have full use of the doctrine of equivalents.  In an infringement proceeding, any claim that is granted as originally filed covers not only the literal elements in the claims but the equivalents of those elements.  But, an amended claim loses the equivalents.  So, the patent practitioner should exercise caution and prudence when amending claims.  Usually, a claim is amended during patent prosecution to clarify the meaning of a claim element, or to narrow or broaden the extent of a claim element in light of art that is cited by the Examiner.  As the Sage ruling above warns us, we have the opportunity to negotiate broader claims during prosecution.  If we don’t take advantage of this opportunity to establish a desired breadth of any claim element amended, we give up that broader breadth.

Some examples may illuminate.  In an electronics patent application, suppose the claim as originally filed recites MOS transistors.  But, the specification teaches that bipolar transistors could also be used in a circuit, as could relays, etc.  If the claim as originally filed is granted, it may be possible to argue that the claim covers other types of transistors and also relays and so on, as these are equivalent to the MOS transistors recited in the claim.  If, during prosecution, the claims are amended to recite NMOS transistors (e.g., because some of the art cites a PMOS transistor embodiment and there is good reason to argue that an NMOS embodiment is not shown in the art), then the claims only cover NMOS transistors.  It will not be possible to argue that the claim covers other types of transistors and also relays, because these equivalents have been surrendered in the amendment.

In a mechanical patent application, suppose the claim as originally filed recites threaded fasteners.  But, the specification teaches that nails, welding, rivets, etc. could also be used to hold something together.  If the claim is amended to recite nuts and bolts, instead of threaded fasteners, then screws, which are not nuts and bolts, and nails and rivets, etc. are surrendered through loss of the equivalents.

Now, supposing in each of these cases, there are other arguments to be made that differentiate the claims from the art, and these other arguments don’t depend on the narrowing as described above.  If the patent practitioner carelessly leaves the above amendments in place, the equivalents are surrendered needlessly, and the issued patent is narrower than was necessary in light of the cited art.  This situation is to be avoided. What should a practitioner do?

When other arguments are found successful against cited art, one strategy is to revisit previous amendments and carefully consider whether a broadening amendment could then be made so that the literal equivalents are captured in the claims.  In the electronics example, suppose an amendment is made elsewhere in the claim, and the limitations regarding NMOS transistors are amended to recite transistors, or better still, switches (provided the specification explains that various types of transistors, relays, etc. can be used as switches).  Now, the amended claim element recites switches, and has literal coverage for the types of equivalents the Applicant intends.  In the mechanical example, suppose an amendment is made elsewhere in the claim, and the limitations regarding nuts and bolts are amended to recite fasteners, or attachment, or some other broader term, or a list of devices that fasten or attach two materials together.  Now, the amended claim recites the literal coverage for the types of equivalents the Applicant intends.  This is taking advantage of the opportunity that the above cases suggest is before us.  Failing to take advantage of this opportunity may have dire costs for the Applicant, in terms of lost claims coverage.  Of course, art cited by the Examiner should be considered, as the above tactic of broadening may reintroduce art earlier eliminated by the initial narrowing amendment and arguments.  The broadening tactic is successful only if the claims, as amended as a whole, do not read on any of the art under 35 USC §102 and 35 USC §103.

There are also more subtle aspects to this.  Comparison language such as less than or equal to, greater than or equal to, thresholds and limits may also be subject to the loss of equivalents in amendment.  Words and phrases such as “or”, “and”, “one of” versus “at least one of” or “one or more of” may be subject to strict scrutiny during Markman hearings, and the doctrine of equivalents may have bearing on the scope of the claims.  Watch these carefully, and amend these prudently.  The doctrine of equivalents, and loss thereof through amendments, is a recommended awareness to have in the art of patenting.

DISCLAIMER: Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

© Womble Bond Dickinson | Attorney Advertising

Written by:

Womble Bond Dickinson
Contact
more
less

Womble Bond Dickinson on:

Readers' Choice 2017
Reporters on Deadline

"My best business intelligence, in one easy email…"

Your first step to building a free, personalized, morning email brief covering pertinent authors and topics on JD Supra:
Sign up using*

Already signed up? Log in here

*By using the service, you signify your acceptance of JD Supra's Privacy Policy.
Custom Email Digest
Privacy Policy (Updated: October 8, 2015):
hide

JD Supra provides users with access to its legal industry publishing services (the "Service") through its website (the "Website") as well as through other sources. Our policies with regard to data collection and use of personal information of users of the Service, regardless of the manner in which users access the Service, and visitors to the Website are set forth in this statement ("Policy"). By using the Service, you signify your acceptance of this Policy.

Information Collection and Use by JD Supra

JD Supra collects users' names, companies, titles, e-mail address and industry. JD Supra also tracks the pages that users visit, logs IP addresses and aggregates non-personally identifiable user data and browser type. This data is gathered using cookies and other technologies.

The information and data collected is used to authenticate users and to send notifications relating to the Service, including email alerts to which users have subscribed; to manage the Service and Website, to improve the Service and to customize the user's experience. This information is also provided to the authors of the content to give them insight into their readership and help them to improve their content, so that it is most useful for our users.

JD Supra does not sell, rent or otherwise provide your details to third parties, other than to the authors of the content on JD Supra.

If you prefer not to enable cookies, you may change your browser settings to disable cookies; however, please note that rejecting cookies while visiting the Website may result in certain parts of the Website not operating correctly or as efficiently as if cookies were allowed.

Email Choice/Opt-out

Users who opt in to receive emails may choose to no longer receive e-mail updates and newsletters by selecting the "opt-out of future email" option in the email they receive from JD Supra or in their JD Supra account management screen.

Security

JD Supra takes reasonable precautions to insure that user information is kept private. We restrict access to user information to those individuals who reasonably need access to perform their job functions, such as our third party email service, customer service personnel and technical staff. However, please note that no method of transmitting or storing data is completely secure and we cannot guarantee the security of user information. Unauthorized entry or use, hardware or software failure, and other factors may compromise the security of user information at any time.

If you have reason to believe that your interaction with us is no longer secure, you must immediately notify us of the problem by contacting us at info@jdsupra.com. In the unlikely event that we believe that the security of your user information in our possession or control may have been compromised, we may seek to notify you of that development and, if so, will endeavor to do so as promptly as practicable under the circumstances.

Sharing and Disclosure of Information JD Supra Collects

Except as otherwise described in this privacy statement, JD Supra will not disclose personal information to any third party unless we believe that disclosure is necessary to: (1) comply with applicable laws; (2) respond to governmental inquiries or requests; (3) comply with valid legal process; (4) protect the rights, privacy, safety or property of JD Supra, users of the Service, Website visitors or the public; (5) permit us to pursue available remedies or limit the damages that we may sustain; and (6) enforce our Terms & Conditions of Use.

In the event there is a change in the corporate structure of JD Supra such as, but not limited to, merger, consolidation, sale, liquidation or transfer of substantial assets, JD Supra may, in its sole discretion, transfer, sell or assign information collected on and through the Service to one or more affiliated or unaffiliated third parties.

Links to Other Websites

This Website and the Service may contain links to other websites. The operator of such other websites may collect information about you, including through cookies or other technologies. If you are using the Service through the Website and link to another site, you will leave the Website and this Policy will not apply to your use of and activity on those other sites. We encourage you to read the legal notices posted on those sites, including their privacy policies. We shall have no responsibility or liability for your visitation to, and the data collection and use practices of, such other sites. This Policy applies solely to the information collected in connection with your use of this Website and does not apply to any practices conducted offline or in connection with any other websites.

Changes in Our Privacy Policy

We reserve the right to change this Policy at any time. Please refer to the date at the top of this page to determine when this Policy was last revised. Any changes to our privacy policy will become effective upon posting of the revised policy on the Website. By continuing to use the Service or Website following such changes, you will be deemed to have agreed to such changes. If you do not agree with the terms of this Policy, as it may be amended from time to time, in whole or part, please do not continue using the Service or the Website.

Contacting JD Supra

If you have any questions about this privacy statement, the practices of this site, your dealings with this Web site, or if you would like to change any of the information you have provided to us, please contact us at: info@jdsupra.com.

- hide
*With LinkedIn, you don't need to create a separate login to manage your free JD Supra account, and we can make suggestions based on your needs and interests. We will not post anything on LinkedIn in your name. Or, sign up using your email address.