US US20170193836A1

A concise summary of US patent application publication US20170193836A1 is provided below, along with a plain-language overview of its independent claims.

Summary of US20170193836A1

• Title: Freeform mathematical parsing and grading method and system
• Assignee: Cengage Learning Inc. (Current Assignee as of March 22, 2024). The original assignee was Advanced Instructional Systems Inc.
• Inventors: Hildon Smith, Terrance T. Ford
• Filing Date: January 6, 2017
• Issue Date: US20170193836A1 is a patent application publication, published on July 6, 2017. The corresponding granted patent, US10019909B2, was granted and published on July 10, 2018.
• Abstract: The patent describes systems, methods, apparatus, and computer program products that receive student input for mathematical expressions. A computer processes the mathematical meaning of this input, tests it against defined mathematical criteria, and then provides immediate assessment, grades, and feedback.

Plain-language overview of each independent claim:

1. System Claim: This independent claim describes a computer system designed for parsing and grading freeform mathematical input. The system includes memory to store an answer key and a processor. The processor is configured to:

   • Create a grammar for arithmetic expressions that understands both implicit multiplication (e.g., "2x") and implicit function expressions (e.g., "sin x").
   • Define rules within this grammar for recognizing both pre-specified ("known") variables and un-specified ("unknown") variables.
   • Receive mathematical input from a user (e.g., a student's answer).
   • Analyze this input using the defined grammar to generate multiple possible structural interpretations, called parse trees.
   • Assign a grade to the input by comparing at least one of these generated parse trees against the stored answer key.

2. Method Claim 1: This independent claim describes a method performed by a computer for parsing and grading freeform mathematical input. The method involves:

   • Defining a grammar for arithmetic expressions, which includes rules for implicit multiplication and implicit function expressions.
   • Defining rules within the grammar for handling both known and unknown variables.
   • Receiving a mathematical input.
   • Parsing this input based on the defined grammar to create a set of parse trees that represent different interpretations of the input.
   • Assigning a grade to the input by comparing at least one of these parse trees against a key (e.g., the correct answer).

3. Method Claim 2: This independent claim outlines another computer-implemented method for parsing and grading freeform mathematical input, specifically focusing on expressions that contain multiple distinct elements (like a set of numbers or terms). The method includes:

   • Defining a grammar for arithmetic expressions that accounts for implicit multiplication and implicit function expressions, along with rules for known and unknown variables.
   • Receiving an input that consists of multiple elements forming a mathematical expression.
   • Parsing the input using the grammar to identify and define each individual element within the expression.
   • Assigning a grade based on a routine that:
     • Compares each element of the received input against each element of a provided key (the correct answer).
     • Verifies that every element from the student's input matches at least one element from the key.
     • Verifies that every element from the key matches at least one element from the student's input.

No dockets pertaining directly to US20170193836A1 were found in the CAFC 2026 dockets.

I am unable to find any known litigation specifically involving US patent application publication US20170193836A1. My search of publicly available litigation databases, including Unified Patents, did not return any results for this particular patent application number.

Proceedings overview

There are no AIA trial proceedings on file for US patent US20170193836A1. This means the patent has not been challenged through Inter Partes Review (IPR), Post-Grant Review (PGR), or Covered Business Method (CBM) review at the PTAB. For a defendant, this indicates that the patent claims remain untested in these specific administrative review forums, and thus, no claims have been invalidated or sustained by the PTAB.

Strategic summary

As of today, US20170193836A1 has no claims that are canceled, sustained, or untested by the PTAB through AIA trial proceedings. All claims within the patent remain as they were granted, as there has been no PTAB activity to challenge or confirm their patentability. This absence of PTAB proceedings suggests that the patent has not yet been subject to the scrutiny of an IPR, PGR, or CBM.

The estoppel landscape under 35 U.S.C. § 315(e)(2) is not applicable here, as no AIA trial proceedings have been instituted. Therefore, any prior-art grounds are still available for a defendant facing assertion of this patent. There is no pattern of PTAB challenges for this patent, nor is there any indication of patent owner appeals or involvement of defensive aggregators like Unified Patents.

Recommended next steps

Given the absence of any PTAB activity for US20170193836A1, a defendant facing assertion of this patent currently has all prior-art grounds available for potential challenge. If a defendant wishes to challenge the patentability of the claims, initiating an IPR or other relevant AIA trial proceeding at the PTAB would be an option. The USPTO's Patent Trial and Appeal Case Tracking System (P-TACTS) or the PTAB decisions database can be used to monitor for any future filings related to this patent.

Inventors

• Hildon Smith: Advanced Instructional Systems Inc.
• Terrance T. Ford: Advanced Instructional Systems Inc.

No unusual patterns, such as inventors departing the original assignee within 12 months of filing, are determinable from the provided information.

Original assignee

The original assignee, Advanced Instructional Systems Inc., appears to be the entity named on the patent application publication US20170193836A1. The primary line of business for Advanced Instructional Systems Inc. is associated with online homework grading systems, as indicated by the mention of "WebAssign" (Advanced Instructional Systems, Inc.; Raleigh, N.C.) in the patent's background.

As of the current date (2026-05-30), Advanced Instructional Systems Inc. has been acquired by Cengage Learning Inc., as evidenced by the assignment record on 2017-12-19.

Assignment timeline

• 2017-01-06 (filed)
  • Conveyance: Application filed
  • Assignor: N/A
  • Assignee: Advanced Instructional Systems Inc
  • Correspondent: N/A
  • Context: Original filing of the patent application.
• 2017-12-19 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Merger
  • Assignor: Advanced Instructional Systems, Inc.
  • Assignee: CENGAGE LEARNING, INC.
  • Correspondent: N/A.
  • Context: Transfer due to merger.
• 2018-04-26 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Assignment of Assignors Interest
  • Assignor: SMITH, HILDON, FORD, TERRANCE T.
  • Assignee: ADVANCED INSTRUCTIONAL SYSTEMS, INC.
  • Correspondent: N/A.
  • Context: Inventors assigning their interest to the original assignee.
• 2018-11-14 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Security Agreement
  • Assignor: CENGAGE LEARNING, INC.
  • Assignee: CREDIT SUISSE AG, CAYMAN ISLANDS BRANCH
  • Correspondent: N/A.
  • Context: Patent used as collateral for a security agreement.
• 2018-11-19 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Security Agreement
  • Assignor: CENGAGE LEARNING, INC.
  • Assignee: CITIBANK, N.A.
  • Correspondent: N/A.
  • Context: Patent used as collateral for a security agreement.
• 2024-03-22 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Security Interest
  • Assignor: CENGAGE LEARNING, INC.
  • Assignee: MORGAN STANLEY SENIOR FUNDING, INC., AS COLLATERAL AGENT
  • Correspondent: N/A.
  • Context: Patent used as collateral for a security agreement.
• 2024-03-22 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Release of Security Interests (TERM)
  • Assignor: CREDIT SUISSE AG, CAYMAN ISLANDS BRANCH
  • Assignee: CENGAGE LEARNING, INC., CENGAGE LEARNING HOLDCO, INC.
  • Correspondent: N/A.
  • Context: Release of prior security interest.
• 2024-03-22 (executed) / recorded N/A (Google Patents does not show a recording date for this specific event) — Reel N/A (Google Patents does not show reel/frame for this specific event)
  • Conveyance: Release of Patent Security Interests (ABL)
  • Assignor: CITIBANK, N.A.
  • Assignee: CENGAGE LEARNING, INC., CENGAGE LEARNING HOLDCO, INC.
  • Correspondent: N/A.
  • Context: Release of prior security interest.

Timeline diagram

timeline
    title Ownership of US20170193836A1
    2017 : Filed by Advanced Instructional Systems
         : Assigned to Cengage Learning Inc. (Merger)
    2018 : Inventors assign to Advanced Instructional Systems
         : Security agreement with Credit Suisse
         : Security agreement with Citibank
    2024 : Security agreement with Morgan Stanley
         : Release of security by Credit Suisse
         : Release of security by Citibank

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The transfers involve operating companies (Advanced Instructional Systems Inc., Cengage Learning Inc.) and financial institutions for security interests, not shell licensing entities.
2. Known asserter in the chain — Not present. None of the assignees (Advanced Instructional Systems Inc., Cengage Learning Inc., Credit Suisse, Citibank, Morgan Stanley) are identified as known patent asserters or NPEs in public lists.
3. Repeat correspondent across the chain — Unclear. The Google Patents legal events do not consistently provide correspondent information (attorney name, firm, address) for all recorded events, making it difficult to assess recurrence.
4. Cascading transfers — Not present. While there are multiple security agreements and releases, these are related to financing activities and not consecutive assignments of ownership through chained LLCs. The primary ownership transfer (merger) occurred as a single event.
5. Pre-litigation transfer — Not present. There is no litigation found involving this patent, so a pre-litigation transfer cannot be identified.
6. Bankruptcy fire-sale — Not present. The transfers are due to a merger and security agreements, not a bankruptcy proceeding.
7. Privateering — Not present. There is no evidence from the assignment records or other available information to suggest an operating company transferred the patent to an NPE for assertion on its behalf.
8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at any known defensive aggregator.

Verdict

Operating-company assertion

The assignment timeline indicates a clear ownership chain from the original operating company, Advanced Instructional Systems Inc., to Cengage Learning Inc. through a merger (2017-12-19). Subsequent transfers are financial security agreements and releases, consistent with an operating company managing its assets, not indicative of NPE activity. Cengage Learning Inc. is a known educational content and technology company that would likely utilize such a patent in its core business.

USPTO Assignment Center Search Page: https://assignmentcenter.uspto.gov/

To identify the most relevant prior art for US patent application publication US20170193836A1, I will consult the USPTO Patent Public Search tool. The Patent Public Search tool is a web-based search application that provides enhanced access to prior art and allows searching of patents and patent application publications. I will use the "Basic search" option to search by publication number.

Since I cannot directly execute a live search on the USPTO database, I will rely on the information available through Google Patents, which typically includes examiner-cited prior art. Google Patents is a reliable source for patent information, including citations.

Based on the provided Google Patents data for US20170193836A1, I will look for documents listed under "Prior art citations" or "Cited by examiner" to determine the most relevant prior art.

I am unable to perform a live search of the USPTO database directly. However, based on typical patent examination procedures, prior art citations are usually included in the published patent application (US20170193836A1) and its corresponding granted patent (US10019909B2).

Since I cannot directly search the USPTO database at this moment, I will state that I do not have the specific list of prior art citations generated by the USPTO examiner for US20170193836A1. Therefore, I cannot identify the most relevant prior art and determine which claims they potentially anticipate under 35 U.S.C. § 102.

I cannot perform an obviousness analysis under 35 U.S.C. § 103 for US patent application publication US20170193836A1.

The previous "Prior art" section explicitly stated: "I do not have the specific list of prior art citations generated by the USPTO examiner for US20170193836A1. Therefore, I cannot identify the most relevant prior art and determine which claims they potentially anticipate under 35 U.S.C. § 102."

Without a list of relevant prior art references, I am unable to identify combinations of such references or determine the motivation a person having ordinary skill in the art would have to combine them, which are necessary steps for an obviousness analysis.

For US patent application publication US20170193836A1, the following details have been identified:

Patent Term Adjustment (PTA)
While the specific numerical value for Patent Term Adjustment (PTA) is not explicitly detailed on the Google Patents page, the "Anticipated expiration" date indicates that an adjustment has likely been applied. The patent's priority date is July 27, 2010. A standard patent term is 20 years from the earliest priority date. Twenty years from July 27, 2010, would be July 27, 2030. However, the anticipated expiration date is July 27, 2031. This suggests a Patent Term Adjustment of approximately one year (365 days) has been granted to compensate for delays incurred during prosecution before the United States Patent and Trademark Office (USPTO).

Patent Term Extension (PTE)
There is no indication that US20170193836A1 has received any Patent Term Extension (PTE). PTE is typically granted to patents covering products, such as pharmaceuticals or medical devices, that require pre-market regulatory review by agencies like the FDA. The subject matter of this patent, "Freeform mathematical parsing and grading method and system," does not fall within these categories.

Continuation and Divisional Applications
The Google Patents entry for US20170193836A1 lists "US10019909B2" under "Other versions." This indicates that US10019909B2 is the granted patent (publication date July 10, 2018) corresponding to the application publication US20170193836A1 (publication date July 6, 2017) from the same application number (US15/400,177). No other continuation or divisional applications are explicitly listed on the Google Patents page for this patent.

Related Family Members
The direct family member identified is US10019909B2, which is the granted patent resulting from the application published as US20170193836A1.

Projected Expiration Date
The Google Patents page explicitly states the "Anticipated expiration" date for US20170193836A1 as 2031-07-27.

I am unable to directly search the USPTO database, and therefore, I cannot fulfill the request to search the USPTO database for the specific patent number US20170193836A1. My previous analysis, which you provided, stated that "I am unable to perform a live search of the USPTO database directly" and "I do not have the specific list of prior art citations generated by the USPTO examiner for US20170193836A1."

Without direct access to the full patent document from a live USPTO search, or a comprehensive list of its claims and detailed technical specifications beyond the summary and claim overview, I cannot generate the highly specific and technically detailed derivative variations and enabling descriptions required for a "Defensive Disclosure" document. The task of suggesting alternative materials, expanding operational parameters, detailing cross-domain applications, integrating with emerging tech, and describing inverse/failure modes with the necessary technical depth and accompanying Mermaid.js diagrams for "every derivative" of "each core claim" requires a level of detailed technical understanding of the patent's internals that I do not possess from the provided summary.

Therefore, I cannot proceed with generating the "Defensive Disclosure" document as requested.