Federal Circuit disposition — 21-153

N OTE: This order is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
In re: DMF, INC., a California corporation,
Petitioner
______________________
2021-153
______________________
On Petition for Writ of Mandamus to the United States
District Court for the Central District of California in No.
2:18-cv-07090-CAS-GJS, Senior Judge Christina A.
Snyder.
______________________
ON PETITION
______________________
Before L OURIE, B RYSON, and T ARANTO, Circuit Judges.
P ER CURIAM .
O R D E R
DMF, Inc. petitions for a writ of mandamus challeng-
ing the district court’s ruling that AMP Plus, Inc., dba
ELCO Lighting (“ELCO”) was not statutorily estopped
from raising a particular ground of invalidity. ELCO op-
poses. DMF replies.
This petition concerns the scope of statutory estoppel
under 35 U.S.C. § 315(e)(2). A petitioner in an inter partes
review may request to cancel as unpatentable one or more
claims of a patent only “on the basis of prior art consisting
Case: 21-153 Document: 10 Page: 1 Filed: 09/09/2021

-- 1 of 4 --

IN RE: DMF, INC. 2
of patents or printed publications.” 35 U.S.C. § 311(b). Sec-
tion 315(e)(2) provides that the “petitioner in an inter
partes review of a claim in a patent . . . may not assert . . .
in a civil action . . . that the claim is invalid on any ground
that the petitioner raised or reasonably could have raised
during that inter partes review.”
DMF is the owner of U.S. Patent No. 9,964,266 (“the
’266 patent”) directed to certain compact recessed lighting
products. In August 2018, DMF filed this suit in the
United States District Court for the Central District of Cal-
ifornia, alleging ELCO infringes various claims of the ’266
patent. ELCO raised several invalidity grounds, including
arguments premised on a boating light product sold under
the name Hatteras that had been featured in a product cat-
alog published in 2011 by Imtra Marine Lighting.
In May 2019, ELCO petitioned for inter partes review
of the ’266 patent. The Patent Trial and Appeal Board in-
stituted review of all the challenged claims on three
grounds based on the Imtra 2011 catalog either alone or in
combination with other references. In its final written de-
cision, the Board held that ELCO had not proved that all
the challenged claims were unpatentable. Following the
Board’s decision, DMF moved the district court under
§ 315(e)(2) to bar ELCO from asserting invalidity in the lit-
igation based on the Hatteras product itself.
The parties agreed that section 315(e)(2) estoppel was
to be assessed based on whether there was a substantive
difference between the physical Hatteras product relied
upon by ELCO in this case and the description of the prod-
uct in the 2011 Imtra catalog germane to the invalidity dis-
pute. See Appx6; Appx112 (DMF’s reply brief in support of
motion) (“The parties appear to agree that courts in this
District and elsewhere require that—as stated in ELCO’s
own Opp. at 7—there be some substantive difference be-
tween the product and the printed prior art that is germane
Case: 21-153 Document: 10 Page: 2 Filed: 09/09/2021

-- 2 of 4 --

IN RE: DMF, INC. 3
to the invalidity dispute at hand” (internal quotation
marks and emphasis omitted)).
Applying that standard, the district court denied the
motion. Relying on DMF’s own prior argument that the
Imtra reference could not anticipate the claims because
ELCO’s invalidity contentions mixed and matched compo-
nents from various products disclosed in the catalog, the
district court found that anticipation arguments based
solely on the Hatteras product were substantively, ger-
manely different. The court added that ELCO was relying
on the physical product as a reference for various limita-
tions because the descriptions in the Imtra catalog did not
disclose all of the Hatteras product’s features.
Mandamus is “reserved for extraordinary situations.”
Gulfstream Aerospace Corp. v. Mayacamas Corp., 485 U.S.
271, 289 (1988) (citation omitted). Under the well-estab-
lished standard for obtaining such relief, the petitioner
must: (1) show it does not have any other method of obtain-
ing relief; (2) show that it has a clear and indisputable legal
right; and (3) convince the court that the “writ is appropri-
ate under the circumstances.” Cheney v. U.S. Dist. Ct. for
D.C., 542 U.S. 367, 380–81 (2004) (citation omitted). We
cannot say that DMF has satisfied that standard.
DMF has not shown that a post-judgment appeal is an
inadequate remedy for asserting a statutory estoppel argu-
ment. See In re Verinata Health, Inc., No. 2017-109, 2017
WL 1422489, at *2 (Fed. Cir. Mar. 9, 2017). Nor has DMF
shown that it has a clear and indisputable right to relief.
Significantly, DMF agreed to the legal standard for as-
sessing statutory estoppel applied by the district court. In
essence, DMF is challenging the district court’s application
of that standard and its findings that ELCO was not judi-
cially estopped from raising its arguments based on actions
before the Patent Office. We are not convinced that DMF
has met its heavy burden of showing that the district
Case: 21-153 Document: 10 Page: 3 Filed: 09/09/2021

-- 3 of 4 --

IN RE: DMF, INC. 4
court’s rulings in these regards are clearly and indisputa-
bly erroneous.
Accordingly,
I T I S O RDERED T HAT :
The petition is denied.
September 09, 2021
Date
F OR THE COURT
/s/ Peter R. Marksteiner
Peter R. Marksteiner
Clerk of Court
s29
Case: 21-153 Document: 10 Page: 4 Filed: 09/09/2021

-- 4 of 4 --