Patent claim construction involves an analysis of intrinsic evidence primarily, and then extrinsic evidence as needed.
Intrinsic evidence includes the following, in this priority order: patented claims, patent specification, and prosecution history. With regard to the prosecution history, this includes not only the prosecution history of the reviewed patent, but also the prosecution histories of all US family members — that is, prior related US applications, prior related CIPs, related US siblings, related US children, and related US grandchildren. For prosecution history review, focus is placed on office actions and office action responses, and reviews look for the possible presence of two types of estoppel: 1) Argument-based prosecution history estoppel where the applicant explicitly indicates claim interpretation through arguments made in office action responses; and 2) Amendment-based prosecution history estoppel where a narrowing amendment is “made for a ‘substantial reason related to patentability’ when the record does not reveal the reason for the amendment.” (Festo)
Extrinsic evidence includes, for example: dictionaries and expert / inventor testimony. Extrinsic evidence may be considered to inform claim construction based upon the intrinsic evidence, but in most situations intrinsic evidence alone suffices to construe claims, and in many cases it is improper to rely on extrinsic evidence at all.
The following is a non-exhaustive set of terms commonly used in patent claim analysis. This list is not meant to be comprehensive, nor is it meant to cover all terminology for patents in general, patenting processes, or patent litigation (e.g., terms like clearance, IDS, post-grant proceedings, licensing, treble damages, etc.). Descriptions have a US-based focus and so are not necessarily applicable for other jurisdictions.
Concentration is placed on those terms most used in the course of patent analysis, where this analysis always focuses on the patented claims. The list will be supplemented over time, and suggestions for additional terms are welcomed.
- Antecedent basis: A claim term (word or phrase) is referred to in a definite form using “the” or “said” and has been been previously introduced in the current claim or in an ancestor claim using the same term. Lack of antecedent basis can lead to claim scope being indefinite. Also, the patent specification (per 35 USC 112) needs to provide guidance on the meaning of claim terms (i.e., support or antecedent basis), although the same words need not be used therein.
- Anticipation: A specific type of description or event which demonstrates that a claimed invention does not meet legal novelty requirements for patenting. Anticipation is determined on a claim-by-claim basis, and a single prior art reference (e.g., a printed publication) or event (such as a sale) must disclose every claimed limitation, whether explicitly or inherently.
- Beauregard: A claim type that claims an article of manufacture embodied as a computer-readable medium (CRM) and associated instructions. The name originates from a Federal Circuit case In re Beauregard (1995). However, a more recent case at the Federal Circuit in 2012 (Digital-Vending Services International, LLC v. The University of Phoenix, Inc.) interpreted Beauregard claims as method claims rather than as apparatus or composition of matter claims. Further complicating scope interpretation of Beauregard claims is that the USPTO now instructs examiners to reject Beauregard claims because computer-readable media can include signals, which were found to not be patentable subject matter under 35 USC 101 in the Federal Circuit case of In re Nuijten (2007). To get around this type of invalidity, the computer-readable media should explicitly be limited to be “non-transitory”.
- Body: The portion of a patent claim which recites claimed elements and describes how these elements interoperate in order to form a claimed invention. The claim body follows the preamble (introduction) and the transition phrase (link).
- Claim construction: Interpretation and determination of the meaning of a patent claim. Construing the proper meaning of a claim is a necessary step prior to determination of potential use.
- Claim type/category: A category covered by a given claim. 35 USC 101 indicates the following basic categories as statutory classes: “process, machine, manufacture, or composition of matter”. A claim covering an activity (process or method) is often referred to as a “process claim”, a “method claim”, or a “use claim”. A claim covering a physical entity such as a product or apparatus (e.g., machine, article, composition, device, system, etc.) is often referred to as a “product claim” or an “apparatus claim”. My Patent Claims Tree tool attempts to determine the type/category of claim for each independent claim based on semantic analysis of language used within the claims. The claim category for a given claim determines its scope and coverage of use.
- Dependent claim: A claim which depends upon at least one other claim and which inherits limitations from its ancestor claims. A dependent claim provides additional specificity and claims a narrower embodiment.
- Direct infringement: This occurs when a party makes, uses, sells, offers to sell, or imports a patented invention in the United States during the term of the associated patent. See also “Indirect infringement” and “Divided use/infringement”.
- Divided use/infringement (multi-actor): Joint infringement when two or more different parties together make, use, sell, or offer to sell a solution that would be judged to infringe upon a patented claim.
- Doctrine of claim differentiation: A rule that every claim in a patent is presumed to have different scope from every other claim. This doctrine means that if a dependent claim of a parent claim specifically has narrower limitations, then the parent claim must necessarily be different – that is, it has a broader interpretation. As an example, for an independent claim that recites a chair with a plurality of legs, with the independent claim having an associated dependent claim requiring a chair with 4 legs, the independent claim is therefore not limited to what is recited in the dependent claim. The dependent claim in this example protects chairs with 4 legs specifically, and therefore the independent claim must logically cover chairs not only with 4 legs, but also chairs having any number of legs greater than one (i.e., a “plurality”). It would be improper to read the 4-leg limitation into the independent claim.
- Doctrine of equivalents: A legal rule that allows a court to hold a party liable for patent infringement even when every element of a patented claim does not literally read on a product or process. Equivalents can be determined when alterations are “insubstantial”, though there are many limitations to the doctrine of equivalents.
- Element: A component of the claim body indicating a part, step, structure, substance, etc. that together with the other claim elements forms the process, machine, article of manufacture, or composition of matter named in the claim preamble.
- Extrinsic evidence: Evidence and support from sources external to the patent itself and its associated prosecution history. Extrinsic evidence may include expert or inventor testimony/opinion, dictionaries, and the like. Normally, review of intrinsic evidence alone suffices to resolve any ambiguity in a claim term, but extrinsic evidence may in some cases inform claim construction based upon the intrinsic evidence.
- Independent claim: A standalone claim that does not refer to or depend upon another claim. An independent claim may have zero or more dependent claims which inherent limitations from it. An independent claim is therefore broader than all its dependent claims.
- Indirect infringement: Here, a party induces another party to directly infringe a patent (inducement) or the party contributes to the direct infringement of the patent by another party (contributory infringement). A party is a contributory infringer only if the party provides a component of a patented invention, and the party knew that the combination for which the component was especially designed was both patented and infringing, and the component must not be a staple article or commodity of commerce suitable for substantial non-infringing use.
- Interpretation: Determination of the meaning of a patent claim. Construing the proper meaning of a claim is a necessary step prior to determination of potential use. See also “Claim construction” and “Markman”.
- Intrinsic evidence: Evidence and support from 1) Claims, 2) Specification, 3) Prosecution History, in that priority order, for determining claim interpretation. With regard to #3, the prosecution history (aka file history, file wrapper, etc.), this includes not only the prosecution history of the specific patent, but also the prosecution histories of all its US family members — i.e., prior related US applications, prior related CIPs, related US siblings, related US children, and related US grandchildren.
- Invalidity: A determination that a patent claim should not have issued due to the associated claimed invention not having been novel or nonobvious, requiring clear and convincing evidence because there is a presumption of validity bestowed on an issued patent. Claims can also be found invalid through other means beyond anticipation or obviousness.
- Limitation: A limitation often refers to an adjective, adverb, or other phrase that modifies a claim element. However, many patent professionals use the term “limitation” interchangeably with the term “element”.
- Markman: A pretrial hearing in which a judge determines appropriate patent claim interpretations as a matter of law.
- Means-Plus-Function (MPF or M+F): A type of claim language which claims a structure only in terms of its functionality. In the US, means-plus-function claims are provided for in 35 USC 112, paragraph 6. Whereas this type of claim was often used to broadly encompass various structures, MPF claims are now construed much more narrowly, encompassing only those structures defined within the patent specification, along with equivalents with insubstantial difference. As a result, and due to the scope uncertainty of MPF claims, this type of claim has fallen more out of use in recent years. Also, while claim construction is a question of law, a determination of the scope of equivalents under 35 USC 112, paragraph 6 is a question of fact (therefore requiring a jury decision).
- Non-obviousness: A patentability requirement which mandates that a claimed invention must not be obvious in that a person having ordinary skill in the art would not know how to solve the problem for which the claimed invention is provided by using the same solution. This requirement is of course applied inconsistently and is normally the most difficult to apply or defend against, and there are and have been many different factors and tests applied to determine nonobviousness (e.g., “Graham factors”, “Teaching-Suggestion-Motivation” (TSM), etc.).
- Novelty: A patentability requirement which mandates that a claimed invention must not have been known to the public before the patent’s priority date (there are some specific date exceptions). Otherwise, the claimed invention is anticipated if one prior art reference or event discloses all the claim elements and limitations and enables a person having ordinary skill in the art to make and use the claimed invention.
- Preamble: An introductory statement for a patent claim that indicates the type of claim (or statutory class) and that names the product or process claimed.
- Prior art: Information which was publicly available in any form before a specific date that might be of relevance to the originality (novelty and nonobviousness) of a claim.
- Prosecution history (file history, file wrapper): Patent prosecution is the interaction between a patent applicant and a patent office with regard to a patent or patent application, and the prosecution history is the collection of these interactions between the applicant (or its representatives) and the office. For the USPTO, the prosecution histories for patents and patent applications is available for retrieval and review through PAIR. Public PAIR provides access to patent histories for published patent documents (usually after 18 months following the priority date), and Private PAIR additionally provides access to prosecution histories for those patent documents that are currently unpublished.
- Subject matter eligibility: Claimed subject matter is eligible or ineligible to be patented based upon the type of subject matter claimed, independent of requirements pertaining to novelty and non-obviousness. Certain types of subject matter are ineligible for patent protection in the US such as literary works, compilations of data, music compositions, legal documents, forms of energy and signals, natural phenomena, mental processes, and abstract intellectual concepts.
- Transition: A transitional word or phrase between the claim preamble and the claim body. Usually this word is “comprises” or “comprising”.
- Transitory signal: Subject matter that is ineligible for patent protection according to the Federal Circuit In re Nuijten (2007) ruling which concluded that articles of manufacture do not include intangible, incorporeal, transitory entities (which the court indicated that signals are).
- Use / Infringement: A product or process is read upon by a patented claim.
- Written description: Portion of a patent specification which describes, among other things, inventive embodiments. Claim elements and limitations need to be disclosed in the written description in order to be allowed.
I spend a fair amount of my time reviewing wireless air interface and data communications inventions, and so I often need to reference appropriate related standards and specification documents. Below is a very partial list of wireless and general data communications standards and specifications along with their associated website links. I hope you find these references helpful and that these hasten your standards document searches.
LTE (and LTE-Advanced) air interface (E-UTRA): published by 3GPP: http://www.3gpp.org/ftp/Specs/html-info/36-series.htm
UMTS/HSPA air interface (UTRA): published by 3GPP: http://www.3gpp.org/ftp/Specs/html-info/25-series.htm
Wi-Fi (802.11): published by IEEE:
- IEEE 802.11a protocol: http://standards.ieee.org/getieee802/download/802.11a-1999.pdf
- IEEE 802.11b protocol: http://standards.ieee.org/getieee802/download/802.11b-1999.pdf
- IEEE 802.11g protocol: http://standards.ieee.org/getieee802/download/802.11g-2003.pdf
- IEEE 802.11n protocol: http://standards.ieee.org/getieee802/download/802.11n-2009.pdf
- Current release of standard (as of Oct 2013): http://standards.ieee.org/getieee802/download/802.11-2012.pdf
Bluetooth: published by Bluetooth Special Interest Group: https://www.bluetooth.org/Technical/Specifications/adopted.htm
Near Field Communication (NFC): published by NFC Forum: http://www.nfc-forum.org/specs/
WiMAX (802.16): published by IEEE: http://standards.ieee.org/about/get/802/802.16.html
CDMA2000 (incl. EV-DO, etc.): published by 3GPP2: http://www.3gpp2.org/public_html/specs/
Internet communications (e.g., HTTP, SIP, DNS, etc.): published by Internet Engineering Task Force (IETF): http://www.ietf.org/rfc.html
Web application technologies (e.g., HTML, CSS, XML, SOAP, DOM, etc.): published by World Wide Web Consortium (W3C): http://www.w3.org/standards/
SIM/USIM: published by 3GPP: http://www.3gpp.org/ftp/Specs/html-info/31-series.htm
Mobile device APIs (e.g., device management, M2M, etc.): published by Open Mobile Alliance (OMA): http://technical.openmobilealliance.org/Technical/current_releases.aspx
Prior to my attendance and panel participation at the SUITS conference in August 2013, TMC published an interview they did with me titled “Three Areas of Intellectual Property You Need to Understand” — this article is available here: http://www.tmcnet.com/topics/articles/2013/08/15/349616-three-areas-intellectual-property-need-understand.htm. Much of what is published there has been covered in earlier posts on this blog, such as in “Clearance Search Review” and “Invention Disclosure Highlights and Considerations”.
However, there is also additional new perspective pertaining to the biggest misconception in terms of how companies can understand, enforce, and protect their patents and intellectual property. This largest misconception in terms of how companies can understand, enforce, and protect their intellectual property is one held by a large portion of companies’ R&D engineering communities – that is, that an inventor’s novel and non-obvious invention is obvious and one that would have been formulated by any other engineer in a similar situation. This misconception leads to many inventions never being considered for patent protection. The issue can at least partially be overcome by continual inventor training to educate engineers to recognize the features of designed products and services that indicate the desirability of protecting aspects of these designed products and services with patents. This training should include information about patents, their history and intent, patentability rules, and examples of patented solutions within the given company’s technology areas. In particular, patent examples often inspire an “aha moment” within engineers that lead them to become prolific inventors and patent protectors.
More and more web applications typically encrypt communications with a user browser using Transport Layer Security (TLS), making determination of how the web application works more difficult. However, as part of patent analysis it can be quite helpful to peek into client-server communications to better ascertain how functionality works.
Packet capture tools such as Wireshark capture all Ethernet communications at a network adapter, and so cannot see inside encrypted packets like TLS packets used for securely transferring data via Hypertext Transfer Protocol Secure (HTTPS). TLS encrypts packets using symmetric cryptography between communication counterparts, so that unless you’re the NSA it should be challenging to be a “man-in-the-middle” and read the communications in the clear. For this reason, what is needed is insight at a counterpart endpoint, and in the client case for a web application this is the web browser. The web browser itself obviously must be able to encrypt and decrypt communications with a web application server, so it is here that one can capture and analyze HTTPS packets in plaintext format.
There are a variety of browser-specific add-ons that are available to capture and present sent and received HTTPS communications in plaintext format. One example that I have found helpful is HttpFox, an extension for Mozilla-based browsers such as the Firefox browser. HttpWatch is another solution that works for Firefox and on iOS devices (iPhone, iPad) as its own browser.
It should be noted that while browser extensions such as HttpFox are helpful for capturing and analyzing secure encrypted communications with browsers, these are not helpful for decrypting communications to/from other client applications because these other applications are TLS counterpart endpoints that are using cryptography without providing insight into the communications.
I am very often asked to review and comment on patents in 15 minutes or even less. In those cases I normally am not requested to provide too much detail due to lack of time, but of course clients still want relevant feedback about each patent. Clients will typically indicate what aspects they want detailed, but in any case there really is one overarching question — that is, “How likely is use of this patent?” To arrive at an answer (such as an estimated probability), an analyst must first ascertain what the key elements and limitations are, and should do so not only for claim 1 or the shortest independent claim, but for all independent claims. From that assessment, the analyst can then focus on one independent claim for providing comments, though sometimes it’s best to indicate differences in claim scope that could impact assessments.
When I tell other analysts that one really should review all independent claims, even in a 15-minute review, often the response is that I’m crazy. And perhaps I am, and in fact it wasn’t that long ago that I said that 15 minutes wasn’t long enough to analyze all independent claims in a patent. But it bothered me because of all the times that I saw that the most relevant claim was not actually claim 1 (supposedly the “representative” claim) or even the shortest claim. So what could be improved to allow for a fuller review in just 15 minutes, or even less? Disclaimer: this technique will not work for outliers like this exceptional patent application, which has 7,215 claims: http://www.google.com/patents/US20030100451!
The answer for me, which I wish to share with you, is the use of software tools — for now my favorite combination is Google Patents (in a particular format) and my free Patent Claims Tree Google Chrome extension. Google Patents has been around for years, but for a while I found that many patents were missing, and I preferred the presentation and layout of FreePatentsOnline. But over time Google Patents improved, and eventually they modified their layout such that I can hardly envision a better format for efficient review of a patent. This format may continue to evolve over time, and perhaps it will even get better, but it certainly is already great — as of this writing, Google Patents has multiple layouts, but the one I particularly like is the format provided for webpages with the following syntax: http://www.google.com/patents/US<patent_number>. Take a look, for example, at: http://www.google.com/patents/US7654321. The title, abstract, and relevant metadata are all presented at the very top of the page in a compact and easily-readable view.
Just below that is a set of all images, which can be quickly expanded and perused, and sideways images can be easily rotated. All images can be visually scanned in less time that it takes to open the patent’s PDF file!
Then perhaps most elegantly, the patent background and the claims are provided in side-by-side columns. The claims are indeed the most important components of a patent because they define a patent’s scope of rights to exclusion, but claims are often worded in manner that can be difficult to comprehend at first glance. Therefore, a quick review of the background section sets the stage for inventive embodiments and helps to scope the claims for a reader. And now this is where the Patent Claims Tree tool for the Chrome browser comes in — with sufficient resolution/zoom, your Chrome browser can simultaneously present the background, claims, and a claims tree with relevant claims metrics, all side-by-side (basically a three-column display):
I find this presentation to be incredibly helpful and fast. The speed at which patent claims can be reviewed using this presentation is key since time is so limited.
With an appropriate input device such as a mouse with a scroll wheel, it is possible to scroll through the claims in Google Patents while the claims tree remains open. Additionally, note all the helpful information presented at a glance in the claims tree: the number of independent claims, which claims are the independent claims, the shortest independent claim, the relative word counts of the independent claims, the type of claim for each independent claim, the relative amount of dependent claims for each independent claim, and which claims use means-plus-function language. Sure, it’s possible to figure all of that out manually, but just that alone would probably take more than 15 minutes by itself.
Those metrics help in determining which independent claim should receive the bulk of your attention. In the example above (I like to use 7,654,321 because it’s a nice number :)), one can quickly determine that in this case there are six independent claims covering a variety of types of coverage, though the “downhole tool” of claim 21 is by far the shortest claim (by about 60 words), so review should probably start there. After reading that claim, if the claim seems to have sufficient coverage, then probably only cursory reviews of the other independent claims are necessary. There are other possible considerations that can be made at a glance as well — e.g., perhaps the client has indicated that it has a threshold for claim word count, so some claims can be discounted rapidly. Or, maybe only claims with a certain type of coverage are desired, and so the claim type can be used to focus on specific claims. In any case, using the three-column presentation, it is normally quite feasible with most patents to have time to read and understand all independent claims, and therefore pick out the best. If you want to find, for example, all method/process claims, this information is there in the tree. Should supplemental background information be needed, it’s right there. Should a figure or two be helpful for understanding scope, it’s simple and speedy to pop them up without a PDF. Should the priority date need consideration, it’s right there above the images.
This approach works quite well for me, and I bet that it will for you too. I am now quite confident in performing 15-minute patent reviews for most technology areas with which I am familiar. There are exceptions of course, but the techniques and software described above have greatly expedited my reviews, making 15 minutes much more comfortable than they used to feel.
If you have additional efficiency tips, please share them in the comments.
Fairly often when performing patent analysis, particularly when creating claim charts mapping one or more patented claims against a target product or service, I find it helpful to capture and analyze packets sent from a wireless device. Internet Protocol (IP) packet capture when using a personal computer, such as a Windows or Mac computer, is relatively straightforward using a packet capture tool. I have been using Wireshark (formerly Ethereal) for years as my preferred packet capture tool, although there are certainly other available options from which to choose, both paid and free.
Packet capture for packets sent to and from other wireless devices such as smartphones and tablets is not so straightforward, therefore I provide below details of a solution that I leverage so that you can take advantage of this approach as well during your patent analysis. The high-level summary of this solution is to set up a Windows OS computer to use Wireshark to capture packets on a virtual Wi-Fi adapter — see this Microsoft explanation of the solution, termed VirtualWiFi, which I can confirm works for me with Windows 7. Credit goes to Eric Geier for documenting how to set up virtual W-Fi adapters here.
1. In a command prompt (“cmd”), enter the following to set up your hosted network connection: netsh wlan set hostednetwork mode=allow ssid=YourVirtualNetworkName key=YourNetworkPassword — You can set up your SSID (YourVirtualNetworkName) and password (YourNetworkPassword) as you wish, though of course you’ll need to know these when you try to connect from your wireless device that you’re testing.
2. Before enabling the virtual hosted network, configure the physical network adapter to share its Internet access using the Internet Connection Sharing (ICS) feature of Windows. To enable ICS, open the Network Connections window, then right-click the network adapter that is actually connected to the Internet and select Properties. Then select the Sharing tab, check the “Allow other network users to connect through this computer’s Internet connection” checkbox, choose the hosted network connection (that you enabled in step #1) from the drop-down listbox, and click OK.
3. In the command prompt, enter the following to start your hosted network connection: netsh wlan start hostednetwork
4. Open Wireshark and select Capture->Interfaces, and select the adapter for your physical network connection and click Start. You can confirm that you have the correct adapter through comparison of MAC addresses, though the easiest solution is probably just to watch the packet count of adapters when using the target wireless device — the adapter with corresponding increases in packet count is the one to use.
5. Connect to the new hosted Wi-Fi network with the target wireless device and execute the desired application, website, service, etc. on the target device being tested and step through whatever sequence for which you wish to analyze the corresponding packets.
6. Once done with testing and recording, select Capture->Interfaces->Stop in Wireshark to stop packet capture.
7. You will then have a set of packets to analyze, and you’ll need to determine the IP address of the wireless device being tested. There are many different considerations here as far as best approaches to walk through the packet data, such as filtering, stream following, searching, exporting, etc., so I suggest that you reference the documentation that Wireshark provides here.
8. Disable the hosted network through entering the following command in the command prompt: netsh wlan stop hostednetwork
If at any time during the steps above you wish to see the current status of the hosted network, such as the MAC addresses of connected devices, enter the following command in the command prompt: netsh wlan show hostednetwork
Once you have performed steps 1-2 above, on system reset the hosted network will not automatically start up, so you would need to execute this command again: netsh wlan start hostednetwork. In fact, once steps 1-2 have been performed once, from then on you should not have to perform them again for subsequent testing — you can start at step 3.
I hope you enjoy your wireless packet capturing and analysis!