Covidien LP v. Ethicon Endo Surgery Inc

1. Case Identification

• Case #: IPR2013-00209
• Patent #: 8,317,070
• Filed: March 25, 2013
• Petitioner(s): Covidien LP
• Patent Owner(s): Ethicon Endo-Surgery, Inc.
• Challenged Claims: 1-14

2. Patent Overview

• Title: Surgical Stapling Instruments That Produce Staples With Different Formed Heights
• Brief Description: The ’070 patent is directed to surgical stapling instruments and staple cartridges capable of applying staples to tissue. The invention purports to form lines of staples with differing final heights by using staples with different initial, pre-deformation heights.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1-8 and 10-14 by Holsten

• Prior Art Relied Upon: Holsten (Application # 2007/0034666).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Holsten discloses every element of the challenged claims. For independent claims 1 and 8, Holsten was alleged to teach a surgical stapling device with a circular anvil (claim 1) or a non-pivotable anvil (claim 8). Petitioner asserted Holsten discloses a plurality of staples with two distinct pre-deformation heights, where one height is less than the other, which results in staples with different formed lengths upon actuation. Holsten was also shown to disclose staples with prongs extending non-parallelly from the main portion and a staple driver assembly as claimed. For claim 8, Petitioner argued Holsten's disclosure of a staple driver mechanism was supplemented by its express incorporation by reference of Robertson (Patent 5,964,394), which details the firing mechanism.

Ground 2: Anticipation of Claims 8 and 10-14 by Pruitt

• Prior Art Relied Upon: Pruitt (Patent 4,941,623).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Pruitt discloses all features of independent claim 8 and its dependent claims. Pruitt was asserted to teach a surgical stapler with a non-pivotable anvil, a staple cartridge, and a plurality of staples. Crucially, Pruitt explicitly discloses using staples of different sizes (e.g., staples 6 and 7) having different pre-deformation heights to achieve different formed staple lengths, a feature the Patent Owner allegedly admitted was in the prior art during prosecution of a related application. Petitioner contended Pruitt also discloses the claimed staple structure (main portion, two prongs), staple drivers, two rows of staple drivers (claim 10), and a tissue retaining pin (claim 11).

Ground 3: Obviousness of Claims 1-7, 12, and 13 over Pruitt and Viola

• Prior Art Relied Upon: Pruitt (Patent 4,941,623) and Viola (WO 2003/094747).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Pruitt discloses most elements of the claims but teaches a linear, rather than circular, stapler. Viola was asserted to remedy this deficiency by expressly teaching various types of staplers, including circular staplers used for procedures like end-to-end anastomoses. Viola also teaches a staple driver assembly with multiple rings of drivers and the inclusion of a knife for cutting tissue, which maps to the limitations of dependent claims 2 and 7, respectively.
  • Motivation to Combine: A POSITA would combine Pruitt’s staple height variation technology with Viola’s well-known circular stapler design to create a device capable of performing specific circular stapling procedures, such as hemorrhoidal operations or anastomoses. The combination would allow for varied compression on tissue in a circular pattern, which was a known objective.
  • Expectation of Success: A POSITA would have had a high expectation of success because the combination involved applying a known feature (variable staple heights from Pruitt) to a standard device configuration (a circular stapler from Viola) to achieve a predictable result. This was presented as an obvious design choice based on the surgical procedure being performed.

• Additional Grounds: Petitioner asserted numerous additional anticipation and obviousness challenges. These included obviousness of claim 9 over Holsten and Burdorff (Patent 5,697,543) for teaching a slideably movable anvil; obviousness over Pruitt and Conta (Patent 4,304,236) for adding a circular anvil and knife; and anticipation of claims 1-5, 7, 8, and 10-13 by Viola alone. Further alternative grounds were presented using Iwabuchi (Japanese Application # 2001-87272), Robertson, and Green (Patent 3,494,533) to address potential claim construction disputes.

4. Key Claim Construction Positions

• "two prongs extend non-parallelly from the main portion": Petitioner argued this should be construed by its plain meaning as the prongs extending non-parallelly relative to the main portion (backspan), not relative to each other. This construction was asserted to be supported by the specification and prosecution history.
• "formed staple length": Petitioner contended this term should be construed as "formed staple height." This was based on the specification and the Patent Owner's interchangeable use of "length" and "height" throughout prosecution to refer to the post-deformation dimension of the staple.
• "non-pivotable anvil": Petitioner argued this should be construed as "non-rotatable anvil." The specification uses "pivot" to refer to rotation, and it describes a "non-rotatable" anvil as one that can slide but not rotate, which Petitioner mapped to the prior art.

5. Key Technical Contentions (Beyond Claim Construction)

• Ineffective Priority Claim: A central contention was that the ’070 patent is not entitled to its claimed priority date of August 31, 2005. Petitioner argued the parent ’562 application explicitly disclaimed the use of staples with different sizes, framing its invention as an improvement that used identically sized staples to achieve different formed heights. Because the challenged claims of the ’070 patent recite staples with different pre-deformation heights (i.e., different sizes), Petitioner argued they lack written description support in the parent application. This argument, if successful, would establish Holsten (published Feb. 15, 2007) as prior art under §102(a) and/or (e).

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-14 of Patent 8,317,070 as unpatentable.