Trusted Knight Corporation v. International Business Machines Corporation
1:14-cv-01063
D. Del.Nov 19, 2015Background
- Trusted Knight sued IBM and Trusteer alleging infringement of U.S. Patent No. 8,316,445, which claims systems/methods to protect against key‑logger malware (filed Aug. 18, 2014).
- The '445 patent focuses on preventing capture/transmission of keystrokes (e.g., form‑grabbing) by moving/processing data at privileged access levels and "clearing" confidential data before it reaches an internet communication port.
- The parties disputed constructions for four claim phrases appearing in independent claims 1, 22, and 23; the court held a Markman claim‑construction hearing and considered intrinsic and extrinsic evidence.
- Disputes centered on scope of "clearing confidential data" (whether it includes encryption and is limited to form inputs), whether the claim requires continuous monitoring to prevent other hooks at the 0‑Ring level, whether the phrase "in response to the software key logging through the API stack to an internet communication port" is definite, and whether a claim phrase containing a drafting error is correctable or indefinite.
- The court adopted a broad construction for "clearing confidential data," rejected a continuous‑monitoring limitation for 0‑Ring protection, and found two claim phrases indefinite (one for vagueness; one for uncorrectable drafting error).
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Construction of "clearing confidential data" — does "clearing" include encryption and is "confidential data" limited to form inputs? | No construction necessary; if construed, means "removing the meaning from confidential data" (broad; can include encryption). | Means "deleting the contents of confidential form inputs" (narrow; excludes encryption; limited to form fields). | Court: adopt Plaintiff's construction — "removing the meaning from confidential data." Encryption not disclaimed; "data" is not limited to form inputs. |
| "prevents any other hooks from inserting at the 0‑Ring level" — does the claim require continuous monitoring/renegotiation? | No construction necessary; if construed, means preventing other software from occupying the most privileged access level (no continuous monitoring requirement). | Requires "continuously monitoring and negotiating placement" so no other hooks can insert at a more privileged level. | Court: adopt Plaintiff's construction — prevents other software from occupying the most privileged access level; rejecting continuous‑monitoring limitation as improperly limiting. |
| Phrase "in response to the software key logging through the API stack to an internet communication port" — is it definite? | No construction necessary; Plaintiff equates phrase to protecting against form‑grabbing/hook‑based keyloggers (responding to threat rather than a detected event). | Indefinite. Argues unclear what action occurs "in response" or what triggers the response. | Court: Indefinite. Language suggests a specific triggered response but the specification and Plaintiff disavow detection/response to a specific malware event; phrase is ambiguous/surplusage. |
| Phrase "a process of passing the encrypted data to a 3‑ring level where a hook inserted by a hook‑based key logger" — is the drafting error correctable or is the term indefinite? | No construction necessary; concedes missing verb but urges correction to read "where a hook is inserted by" (or equivalent) and that meaning is clear to skilled artisan. | Indefinite. Argues correction is subject to reasonable debate; several plausible fixes would change scope. | Court: Indefinite. Correction is reasonably debatable (multiple plausible readings, and some conflict with the specification's statements about operation absent malware), so court will not reform the claim. |
Key Cases Cited
- Teva Pharm. USA, Inc. v. Sandoz, Inc., 135 S. Ct. 831 (explains role of appellate review for factual findings in claim construction)
- Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir.) (claims are given their ordinary and customary meaning; specification is primary guide)
- Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576 (Fed. Cir.) (specification is usually dispositive for claim meaning)
- Markman v. Westview Instruments, Inc., 517 U.S. 370 (establishes claim construction as a question of law)
- Liebel‑Flarsheim Co. v. Medrad, Inc., 358 F.3d 898 (Fed. Cir.) (do not read claims narrowly based on single embodiment absent clear intent to limit)
- Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120 (indefiniteness standard requires reasonable certainty)
- Renishaw PLC v. Marposs Societa' per Azioni, 158 F.3d 1243 (Fed. Cir.) (construction that aligns with claim language and specification is correct)
- CBT Flint Partners, LLC v. Return Path, Inc., 654 F.3d 1353 (Fed. Cir.) (district courts may correct obvious errors in patent claims but only when not reasonably debatable)