DCT
2:24-cv-00950
Valtrus Innovations Ltd v. Digital Realty Trust Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Valtrus Innovations Ltd. and Key Patent Innovations Ltd. (Ireland)
- Defendant: Digital Realty Trust, Inc. and Digital Realty Trust, L.P. (Maryland / Texas)
- Plaintiff’s Counsel: Reichman Jorgensen Lehman & Feldberg LLP; Findlay Craft, P.C.
- Case Identification: 2:24-cv-00950, E.D. Tex., 11/20/2024
- Venue Allegations: Venue is alleged based on Defendant maintaining a regular and established place of business within the district, specifically its DFW11 and DFW26 data centers, where infringing activities are said to occur.
- Core Dispute: Plaintiff alleges that Defendant’s data center cooling systems and optimization methods infringe three patents related to dynamic environmental control and energy management in data centers.
- Technical Context: The technology concerns systems for efficiently managing the temperature and airflow in large-scale data centers, a critical factor in operational cost and reliability for the cloud computing and data hosting industry.
- Key Procedural History: The complaint alleges that Defendant was put on notice of U.S. Patent No. 7,251,547 via a letter from Plaintiff dated March 29, 2024, which may be relevant to the willfulness allegations for that patent.
Case Timeline
| Date | Event |
|---|---|
| 2002-10-03 | U.S. Patent No. 6,854,284 Priority Date |
| 2003-01-16 | U.S. Patent No. 6,868,682 Priority Date |
| 2004-10-08 | U.S. Patent No. 7,251,547 Priority Date |
| 2005-02-15 | U.S. Patent No. 6,854,284 Issues |
| 2005-03-22 | U.S. Patent No. 6,868,682 Issues |
| 2007-07-31 | U.S. Patent No. 7,251,547 Issues |
| 2021-02-08 | Date of "Benchmark" measurements in accused software report (Compl. p. 12) |
| 2021-02-11 | Date of "Post-Optimisation" measurements in accused software report (Compl. p. 14) |
| 2024-03-29 | Alleged notice of U.S. Patent No. 7,251,547 sent to Defendant |
| 2024-11-20 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,854,284 - "Cooling of data centers," issued February 15, 2005 (’284 Patent)
The Invention Explained
- Problem Addressed: The patent describes conventional data center cooling systems as inefficient because they often operate at maximum capacity based on worst-case scenarios and remove air indiscriminately, leading to unnecessary energy expenditure (’284 Patent, col. 2:1-14).
- The Patented Solution: The invention proposes a more intelligent cooling system that uses a plenum (e.g., the space under a raised floor) to deliver cool air. The system actively senses the pressure of the cooling fluid within the plenum and varies the intake of the main cooling system in response to the sensed pressure, thereby matching cooling effort to demand more efficiently (’284 Patent, Abstract; col. 10:9-24, FIG. 2B).
- Technical Importance: This pressure-based feedback control loop represented a shift from static, brute-force cooling to a more dynamic and responsive approach aimed at reducing the significant energy costs associated with data center operations (’284 Patent, col. 9:8-14).
Key Claims at a Glance
- The complaint asserts independent method claim 10 (Compl. ¶22).
- Essential elements of claim 10 include:
- Activating a cooling system and opening returns that are in fluid communication with a plenum.
- Sensing a pressure of the cooling fluid in the plenum.
- Determining if the sensed pressure is within a predetermined range.
- Varying an intake of the cooling system in response to the sensed pressure falling outside the predetermined range.
- The complaint reserves the right to assert other claims, including dependent claims (Compl. ¶28).
U.S. Patent No. 6,868,682 - "Agent based control method and system for energy management," issued March 22, 2005 (’682 Patent)
The Invention Explained
- Problem Addressed: The patent identifies the inefficiency of conventional cooling systems that measure temperature only at the central cooling unit, not at the locations where heat-producing equipment resides, leading to poor energy management (’682 Patent, col. 2:18-29).
- The Patented Solution: The invention discloses a distributed control system using a "hierarchy of agents." A "first agent" (e.g., a rack-level agent) monitors a local subsystem's temperature and adjusts its cooling. If unable to maintain the desired temperature, it requests a "second agent" higher in the hierarchy (e.g., a row-level or CRAC agent) to assist, for instance, by redistributing cooling fluid (’682 Patent, Abstract; col. 3:1-14, FIG. 4). This creates a scalable, multi-level control architecture.
- Technical Importance: The agent-based hierarchical model provided a framework for decentralized and scalable control, allowing for more granular and intelligent management of cooling resources as data centers grew in size and complexity (’682 Patent, col. 4:10-24).
Key Claims at a Glance
- The complaint asserts independent method claim 1 (Compl. ¶30).
- Essential elements of claim 1 include:
- Receiving sensory data corresponding to a temperature from a subsystem.
- Processing the data by a "first agent in a hierarchy of agents" to check if the subsystem is within a temperature range.
- Adjusting a cooling fluid delivery rate using the first agent.
- Requesting a "second agent from the hierarchy of agents" to process the data if the first agent cannot maintain the temperature, unless the second agent redistributes cooling fluid.
- The complaint reserves the right to assert other claims, including dependent claims (Compl. ¶37).
Multi-Patent Capsule: U.S. Patent No. 7,251,547 - "Correlation of vent tile settings and rack temperatures," issued July 31, 2007 (’547 Patent)
- Technology Synopsis: The patent addresses the problem that in a raised-floor data center, it is difficult to know which vent tiles cool which equipment racks. The invention provides a method to systematically determine this relationship by sequentially closing vent tiles, detecting the resulting temperature changes at rack inlets, and using this data to correlate specific tiles to specific racks, thereby enabling more precise airflow control (Compl. ¶40; ’547 Patent, Abstract).
- Asserted Claims: Independent method claim 1 (Compl. ¶40).
- Accused Features: The complaint alleges that Defendant's use and promotion of EkkoSoft Critical software, which is used for data center optimization, performs the patented method of correlating vent tiles and rack temperatures (Compl. ¶¶42, 51).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are the data centers operated by Digital Realty, including their cooling systems and methods of operation (Compl. ¶¶17, 24). Specific components identified include Computer Room Air Handling (CRAH) units, Trane RTAC chillers, and associated control systems (Compl. ¶¶25, 32). The complaint also accuses methods of data center optimization allegedly performed using EkkoSoft Critical software (Compl. ¶42).
Functionality and Market Context
- The complaint alleges that Digital Realty's data centers employ cooling systems that remove hot air from equipment areas via returns into a plenum, where it is then cooled by CRAH units (Compl. ¶25). A photograph included in the complaint shows a data center interior with a raised floor, which typically creates an underfloor plenum for cold air distribution (Compl. p. 7).
- For temperature control, the complaint alleges the use of multiple chillers operating in series, where one chiller handles a primary load and a second engages to provide additional cooling to meet a system setpoint (Compl. ¶¶34-36). A diagram from a third-party document, reproduced in the complaint, illustrates this "Typical series chiller arrangement" (Compl. p. 10, Figure 3).
- The complaint further alleges that Digital Realty uses or promotes the EkkoSoft Critical software platform to optimize its data centers by correlating vent tile settings with rack temperatures, a process illustrated with thermal maps showing conditions before and after optimization (Compl. ¶¶42-49, pp. 12, 14).
IV. Analysis of Infringement Allegations
’284 Patent Infringement Allegations
| Claim Element (from Independent Claim 10) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| activating a cooling system and opening a plurality of returns... said plurality of returns also being in fluid communication with a plenum | Defendant operates cooling systems (CRAH units) and uses hot air returns that are in fluid communication with a return air plenum. | ¶25 | col. 4:20-22 |
| sensing a pressure of said cooling fluid in the plenum | Defendant's data centers are "controlled or monitored with pressure sensors" in contained spaces like hot and cold aisles. | ¶27 | col. 10:9-11 |
| determining whether said sensed pressure is within a predetermined pressure range | Defendant's cooling systems are controlled with respect to "pressure[] setpoints." | ¶27 | col. 13:54-58 |
| varying an intake of said cooling system through the plurality of returns in response to said sensed pressure falling outside of said predetermined pressure range | Fans within the cooling systems are controlled based on pressure setpoints, implying the intake is varied in response to pressure deviations. | ¶27 | col. 13:58-64 |
Identified Points of Contention
- Technical Question: The complaint's primary evidence for pressure sensing and control is a citation to a Digital Realty patent application (Compl. ¶27, fn. 5). A key question will be whether discovery confirms that the accused data centers actually implement the specific pressure-based feedback loop required by claim 10, or if they primarily use a different control logic (e.g., temperature-based).
- Scope Question: Does the allegedly infringing control of "[f]ans within the cooling systems" (Compl. ¶27) constitute "varying an intake of said cooling system" as required by the claim? The analysis will focus on whether the accused fan control is directly responsive to plenum pressure falling outside a set range, as claimed, or is part of a more general temperature management algorithm.
’682 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| receiving sensory data corresponding to a temperature from a subsystem in a data center | Defendant's Trane chillers receive data from "temperature control sensors." | ¶33 | col. 11:1-2 |
| processing the sensory data by a first agent in a hierarchy of agents to determine if the subsystems in the data center is operating within a predetermined temperature range | A first chiller ("Chiller 2") in a series arrangement processes temperature data to meet a setpoint. The complaint maps this chiller to the "first agent." | ¶¶34-35 | col. 11:2-5 |
| adjusting a delivery rate for a cooling fluid using the first agent to keep the temperature range... within the predetermined temperature range | As system load increases, "Chiller 2 becomes preferentially loaded as it attempt[s] to meet the leaving chilled water setpoint." | ¶35 | col. 3:5-8 |
| requesting a second agent from the hierarchy of agents... when the first agent cannot keep the temperature range... unless the second agent redistributes the cooling fluid | If Chiller 2 cannot meet the setpoint, "Chiller 1 will finish cooling the leaving water." The complaint maps Chiller 1 to the "second agent." | ¶36 | col. 3:8-14 |
Identified Points of Contention
- Scope Question: The central dispute will be whether two physical chillers operating in a series cooling loop can be construed as a "hierarchy of agents." The patent describes agents as entities (potentially software) that process information, have objectives, and communicate, which suggests a level of logical abstraction beyond simple mechanical operation (’682 Patent, col. 13:41-48, 14:8-14).
- Technical Question: Does the accused Trane system's operation meet the specific claimed logic of "requesting a second agent... unless the second agent redistributes the cooling fluid"? The complaint alleges a sequential cooling process, but it may not map directly onto the patent's specific conditional logic for escalating control within the hierarchy.
V. Key Claim Terms for Construction
For the ’284 Patent:
- The Term: "varying an intake of said cooling system"
- Context and Importance: This term is critical because infringement depends on showing that Defendant's systems adjust their overall cooling operation (the "intake") specifically in response to plenum pressure. This distinguishes the claim from general temperature control methods. Practitioners may focus on this term to determine if the accused fan control is the "intake" and if its variation is directly caused by the sensed pressure as claimed.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification discusses varying the speed of the fan 24 and/or the capacity of the compressor 30 as ways to control the cooling system, which could support a broad definition of "intake" (’284 Patent, col. 8:35-41, col. 9:26-30).
- Evidence for a Narrower Interpretation: The claim links the "varying" action directly to the "sensed pressure falling outside of said predetermined pressure range." This suggests a specific causal link, potentially narrowing the term to exclude variations made for other reasons (e.g., direct temperature feedback) (’284 Patent, Claim 10).
For the ’682 Patent:
- The Term: "hierarchy of agents"
- Context and Importance: This is the core inventive concept of the ’682 Patent. The Plaintiff's case hinges on construing this term to read on two physical chillers. The definition will determine whether the patent is limited to software-based or processor-driven control systems or if it can cover staged mechanical systems.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification is not explicitly limited to software. One could argue the hierarchical function is what matters, and that any system with tiered, escalating control meets the definition. The patent abstract itself does not specify software.
- Evidence for a Narrower Interpretation: The detailed description repeatedly discusses agents in terms of processing information, having objectives, making calculations, and communicating (’682 Patent, col. 13:9-14, 14:8-14, 15:40-45). FIG. 4 shows "Rack Agents," "Row Agents," and "CRAC Agents" interacting, which strongly implies a distributed, software-like control structure, not just two pieces of hardware in series.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Digital Realty induces and contributes to the infringement of the ’547 Patent by its customers (Compl. ¶51). The basis for this allegation is that Defendant promotes the use of the infringing EkkoSoft Critical device to its customers, knowing it will be used to perform the patented method (Compl. ¶¶42, 51).
- Willful Infringement: Willfulness is alleged for all three Asserted Patents (Prayer for Relief, ¶B). For the ’547 Patent, the complaint alleges pre-suit knowledge based on a specific notice letter dated March 29, 2024 (Compl. ¶39). For all patents, willfulness is also alleged based on Defendant’s failure to cease infringement after the filing of the lawsuit (Compl. ¶52).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can the term "hierarchy of agents", which the ’682 Patent describes in the context of communicating, objective-driven entities, be construed to cover the staged mechanical operation of two physical chillers as alleged in the complaint? The outcome of this construction may be dispositive for the ’682 Patent.
- A second key question will be one of evidentiary proof: does the accused cooling system in Digital Realty's data centers actually implement the specific pressure-based feedback control loop required by Claim 10 of the ’284 Patent, or is its primary control mechanism based on temperature or other factors?
- Finally, for the ’547 Patent, the dispute will likely focus on a functional comparison: does the accused EkkoSoft Critical software perform the specific steps of the claimed correlation method, particularly the sequential closing of vents and measurement of resulting rack-level temperature changes, as depicted in the complaint’s evidentiary exhibits?