Image from Google’s Project Loon webpage.

Judicial estoppel made a surprise appearance before Judge Freeman on May 18, 2018 when she heard (and denied) Space Data Corporation’s (“Space Data”) motion for partial summary judgment that Alphabet Inc. and Google LLC (collectively, “Google”) are judicially estopped from claiming that Space Data’s asserted claims are invalid.

Space Data accuses Google’s “Project Loon”—a project that uses balloons to provide wireless Internet access to remote locations[1]—of infringing U.S. Patent No. 9,678,193 (“the ’193 patent”).  Google had a patent of its own that covered balloon communication systems, U.S. Patent No. 8,820,678 (“the ’678 patent”), against which Space Data initiated an interference proceeding to establish that its patent had priority over Google’s.  Google did not oppose Space Data’s priority claim and, consequently, the PTAB issued a ruling in Space Data’s favor.

Back in the district court, Space Data tried to leverage the outcome of the interference proceeding to prevent Google from (1) arguing that any reference disclosed during proceedings involving Google’s patents or patent applications, and references disclosing the same subject matter, constitute prior art to the ’193 patent, and (2) challenging the validity of the asserted claims of the ’193 patent under 35 U.S.C. sections 101, 102, or 103.  Given the likeness between the two patents, Space Data argued that Google could not maintain that its invention was patentable during prosecution but then about-face in the district court action to claim Space Data’s identical and earlier-claimed invention was obvious and not novel.

Space Data invoked the rarely-seen judicial estoppel doctrine, which applies where a party takes a position during a legal proceeding (in this case, original prosecution of Google’s ’678 patent and then the interference proceedings), succeeds on that position, then later takes a contrary position.  A party is judicially estopped from taking a position if: (1) the position is “clearly inconsistent” with an earlier position; (2) the party succeeded on the earlier position such that there is a clear perception that either the first or the second court was misled; and (3) the party would gain an unfair advantage or impose a disadvantage on the opposing party.[2]

The Court, however, denied Space Data’s motion because Google’s positions in the interference proceedings and the district court were not inconsistent, let alone “clearly inconsistent.”  During prosecution, the examiner issued a non-final rejection that Google’s ’678 claims were anticipated or obvious over a patent issued to Campbell.[3]  To traverse the rejection, Google added limitations for controlling the altitude of a target balloon based on the desired horizontal movement of the balloon.  The PTO issued the amended claims over Campbell.  In its invalidity contentions before the district court, Google asserted that Campbell disclosed all of the subject matter of the independent claims in Space Data’s ’193 patent except using the altitude to control the horizontal position of the balloon.  Also, Google’s obviousness arguments were predicated on Campbell lacking this feature, Google identified several other references that allegedly did disclose it, and Google explained why a POSITA would be motivated to combine the references to add the feature.  Google’s assertions in its invalidity contentions were therefore consistent with its assertions during prosecution of the ’678 patent.

The Court went on to address the other instances when Google allegedly took inconsistent positions.  Space Data argued that Google took inconsistent positions by arguing that a patent by Aaron in combination with other references rendered the asserted claims obvious because Google conceded during the interference that Aaron did not invalidate claims of the ’678 patent.  But the Court disagreed with Space Data’s recap of the interference proceeding, noting that whether Aaron anticipated or rendered obvious claims was not even at issue in the interference.  Space Data also argued that in Google’s Information Disclosure Statements, Google stated that the prior art listed did not anticipate or render obvious the ’678 patent claims.  Yet the Court found no such statement and cited to the CFR, which states that the filing of an IDS does not constitute an admission that the submitted information is material to patentability.  Lastly, Space Data argued that Google’s inventor declaration for the ’678 patent stated that the invention was Google’s alone and was novel and non-obvious.  Again the Court found no such statement in the document to which Space Data pointed.  The declaration instead stated that the inventors were the first and joint inventors of the subject matter for which patent protection was sought and they have a duty to disclose information material to patentability.

While Judge Freeman did not find that judicial estoppel applied in this case, the attack could potentially be used to effectively limit an accused infringer’s defenses when litigating issues in multiple fora.


Space Data Corporation v. Alphabet Inc., et al., Case No. 5:16-cv-03260-BLF (NC), Dkt. 255 (N.D. Cal. May 18, 2018).



[2]  New Hampshire v. Maine, 532 U.S. 742 (2001).

[3]  U.S. Patent No. 6,167,263.